Synchronized calibration for wireless communication devices
Synchronized calibration for wireless communication devices. A protocol is presented herein that allows for calibration operation(s) by one or more wireless communication devices to mitigate (or eliminate) the disruption caused to the communication medium thereby. A calibration announcement frame is provided by a wireless communication device intending to perform calibration operation(s), and respective receiving wireless communication devices may adaptively determine whether to perform a calibration operation based thereon. In response to a calibration announcement frame, one or more other wireless communication devices may also perform calibration operation(s) (e.g., in accordance with a group calibration event, simultaneously, etc.) or may perform some operations as to minimize any effects that may be incurred during such a calibration operation(s) (e.g., enter into some robust operational mode, power savings mode, etc.). Such a calibration announcement frame may indicate respective time slots (e.g., maintenance window) during which respective wireless communication devices may perform calibration operation(s).
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The present U.S. Utility patent application claims priority pursuant to 35 U.S.C. §119(e) to the following U.S. Provisional patent application which is hereby incorporated herein by reference in its entirety and made part of the present U.S. Utility patent application for all purposes:
1. U.S. Provisional Patent Application Ser. No. 61/491,838, entitled “Media communications and signaling within wireless communication systems,” (Attorney Docket No. BP22744), filed May 31, 2011, pending.
Incorporation by ReferenceThe following standards/draft standards are hereby incorporated herein by reference in their entirety and are made part of the present U.S. Utility patent application for all purposes:
1. WD1: Working Draft 1 of High-Efficiency Video Coding, Joint Collaborative Team on Video Coding (JCT-VC), of ITU-T SG16 WP3 and ISO/IEC JTC1/SC29/WG11, Thomas Wiegand, et al., 3rd Meeting: Guangzhou, CN, 7-15 Oct., 2010, Document: JCTVC-C403, 137 pages.
2. ISO/IEC 14496-10—MPEG-4 Part 10, AVC (Advanced Video Coding), alternatively referred to as H.264/MPEG-4 Part 10 or AVC (Advanced Video Coding), ITU H.264/MPEG4-AVC, or equivalent.
Incorporation by ReferenceThe following IEEE standards/draft IEEE standards are hereby incorporated herein by reference in their entirety and are made part of the present U.S. Utility patent application for all purposes:
1. IEEE Std 802.11™—2007, “IEEE Standard for Information technology—Telecommunications and information exchange between systems—Local and metropolitan area networks—Specific requirements; Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications,” IEEE Computer Society, IEEE Std 802.11™—2007, (Revision of IEEE Std 802.11-1999), 1233 pages.
2. IEEE Std 802.11™—2009, “IEEE Standard for Information technology—Telecommunications and information exchange between systems—Local and metropolitan area networks—Specific requirements; Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications; Amendment 5: Enhancements for Higher Throughput,” IEEE Computer Society, IEEE Std 802.11n™—2009, (Amendment to IEEE Std 802.11™—2007 as amended by IEEE Std 802.11k™—2008, IEEE Std 802.11r™—2008, IEEE Std 802.11y™—2008, and IEEE Std 802.11r™—2009), 536 pages.
3. IEEE P802.11ac™/D1.0, May 2011, “Draft STANDARD for Information Technology—Telecommunications and information exchange between systems—Local and metropolitan area networks—Specific requirements, Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) specifications, Amendment 5: Enhancements for Very High Throughput for Operation in Bands below 6 GHz,” Prepared by the 802.11 Working Group of the 802 Committee, 263 total pages (pp. i-xxi, 1-242).
BACKGROUND OF THE INVENTION1. Technical Field of the Invention
The invention relates generally to communication systems; and, more particularly, it relates to coordinating calibration operations among the various wireless communication devices within such communication systems as to mitigate (or eliminate) any undesirable interference such as may be generated thereby.
2. Description of Related Art
Communication systems are known to support wireless and wire lined communications between wireless and/or wire lined communication devices. Such communication systems range from national and/or international cellular telephone systems to the Internet to point-to-point in-home wireless networks. Each type of communication system is constructed, and hence operates, in accordance with one or more communication standards. For instance, wireless communication systems may operate in accordance with one or more standards including, but not limited to, IEEE 802.11x, Bluetooth, advanced mobile phone services (AMPS), digital AMPS, global system for mobile communications (GSM), code division multiple access (CDMA), local multi-point distribution systems (LMDS), multi-channel-multi-point distribution systems (MMDS), and/or variations thereof.
Depending on the type of wireless communication system, a wireless communication device, such as a cellular telephone, two-way radio, personal digital assistant (PDA), personal computer (PC), laptop computer, home entertainment equipment, et cetera communicates directly or indirectly with other wireless communication devices. For direct communications (also known as point-to-point communications), the participating wireless communication devices tune their receivers and transmitters to the same channel or channels (e.g., one of the plurality of radio frequency (RF) carriers of the wireless communication system) and communicate over that channel(s). For indirect wireless communications, each wireless communication device communicates directly with an associated base station (e.g., for cellular services) and/or an associated access point (e.g., for an in-home or in-building wireless network) via an assigned channel. To complete a communication connection between the wireless communication devices, the associated base stations and/or associated access points communicate with each other directly, via a system controller, via the public switch telephone network, via the Internet, and/or via some other wide area network.
For each wireless communication device to participate in wireless communications, it includes a built-in radio transceiver (i.e., receiver and transmitter) or is coupled to an associated radio transceiver (e.g., a station for in-home and/or in-building wireless communication networks, RF modem, etc.). As is known, the receiver is coupled to the antenna and includes a low noise amplifier, one or more intermediate frequency stages, a filtering stage, and a data recovery stage. The low noise amplifier receives inbound RF signals via the antenna and amplifies them. The one or more intermediate frequency stages mix the amplified RF signals with one or more local oscillations to convert the amplified RF signal into baseband signals or intermediate frequency (IF) signals. The filtering stage filters the baseband signals or the IF signals to attenuate unwanted out of band signals to produce filtered signals. The data recovery stage recovers raw data from the filtered signals in accordance with the particular wireless communication standard.
As is also known, the transmitter includes a data modulation stage, one or more intermediate frequency stages, and a power amplifier (PA). The data modulation stage converts raw data into baseband signals in accordance with a particular wireless communication standard. The one or more intermediate frequency stages mix the baseband signals with one or more local oscillations to produce RF signals. The power amplifier amplifies the RF signals prior to transmission via an antenna.
Typically, the transmitter will include one antenna for transmitting the RF signals, which are received by a single antenna, or multiple antennae (alternatively, antennas), of a receiver. When the receiver includes two or more antennae, the receiver will select one of them to receive the incoming RF signals. In this instance, the wireless communication between the transmitter and receiver is a single-output-single-input (SISO) communication, even if the receiver includes multiple antennae that are used as diversity antennae (i.e., selecting one of them to receive the incoming RF signals). For SISO wireless communications, a transceiver includes one transmitter and one receiver. Currently, most wireless local area networks (WLAN) that are IEEE 802.11, 802.11a, 802.11b, or 802.11g employ SISO wireless communications.
Other types of wireless communications include single-input-multiple-output (SIMO), multiple-input-single-output (MISO), and multiple-input-multiple-output (MIMO). In a SIMO wireless communication, a single transmitter processes data into radio frequency signals that are transmitted to a receiver. The receiver includes two or more antennae and two or more receiver paths. Each of the antennae receives the RF signals and provides them to a corresponding receiver path (e.g., LNA, down conversion module, filters, and ADCs). Each of the receiver paths processes the received RF signals to produce digital signals, which are combined and then processed to recapture the transmitted data.
For a multiple-input-single-output (MISO) wireless communication, the transmitter includes two or more transmission paths (e.g., digital to analog converter, filters, up-conversion module, and a power amplifier) that each converts a corresponding portion of baseband signals into RF signals, which are transmitted via corresponding antennae to a receiver. The receiver includes a single receiver path that receives the multiple RF signals from the transmitter. In this instance, the receiver uses beam forming to combine the multiple RF signals into one signal for processing.
For a multiple-input-multiple-output (MIMO) wireless communication, the transmitter and receiver each include multiple paths. In such a communication, the transmitter parallel processes data using a spatial and time encoding function to produce two or more streams of data. The transmitter includes multiple transmission paths to convert each stream of data into multiple RF signals. The receiver receives the multiple RF signals via multiple receiver paths that recapture the streams of data utilizing a spatial and time decoding function. The recaptured streams of data are combined and subsequently processed to recover the original data.
With the various types of wireless communications (e.g., SISO, MISO, SIMO, and MIMO), and particularly within communication devices that may employ multiple communication paths therein, the present art does not provide an adequate solution by which various communications maybe performed and operated in a communication device without deleterious affecting one another.
In the context of wireless communications and particularly the transmission and receipt of signals therein that include media content (e.g., video, audio, etc.), certain considerations should be made that are not necessary within non-media related signaling. For example, certain non-media related signals do not suffer significant degradation of performance from latency, delay, etc. Often times, such media related content communications are relatively more time critical than non-media related content communications. Particularly in the context of wireless communications, the present art does not provide an adequate means by which media related content communications may be effectuated in a robust, reliable, and perceptually acceptable manner.
Within communication systems, signals are transmitted between various communication devices therein. The goal of digital communications systems is to transmit digital data from one location, or subsystem, to another either error free or with an acceptably low error rate. As shown in
Referring to
To reduce transmission errors that may undesirably be incurred within a communication system, error correction and channel coding schemes are often employed. Generally, these error correction and channel coding schemes involve the use of an encoder at the transmitter end of the communication channel 199 and a decoder at the receiver end of the communication channel 199.
Any of various types of ECC codes described can be employed within any such desired communication system (e.g., including those variations described with respect to
Generally speaking, when considering a communication system in which video data is communicated from one location, or subsystem, to another, video data encoding may generally be viewed as being performed at a transmitting end of the communication channel 199, and video data decoding may generally be viewed as being performed at a receiving end of the communication channel 199.
Also, while the embodiment of this diagram shows bi-directional communication being capable between the communication devices 110 and 120, it is of course noted that, in some embodiments, the communication device 110 may include only video data encoding capability, and the communication device 120 may include only video data decoding capability, or vice versa (e.g., in a uni-directional communication embodiment such as in accordance with a video broadcast embodiment).
Referring to the communication system 200 of
Within each of the transmitter 297 and the receiver 298, any desired integration of various components, blocks, functional blocks, circuitries, etc. Therein may be implemented. For example, this diagram shows a processing module 280a as including the encoder and symbol mapper 220 and all associated, corresponding components therein, and a processing module 280 is shown as including the metric generator 270 and the decoder 280 and all associated, corresponding components therein. Such processing modules 280a and 280b may be respective integrated circuits. Of course, other boundaries and groupings may alternatively be performed without departing from the scope and spirit of the invention. For example, all components within the transmitter 297 may be included within a first processing module or integrated circuit, and all components within the receiver 298 may be included within a second processing module or integrated circuit. Alternatively, any other combination of components within each of the transmitter 297 and the receiver 298 may be made in other embodiments.
As with the previous embodiment, such a communication system 200 may be employed for the communication of video data is communicated from one location, or subsystem, to another (e.g., from transmitter 297 to the receiver 298 via the communication channel 299).
Wireless communication devices 322, 323, and 324 are located within an independent basic service set (IBSS) area and communicate directly (i.e., point to point). In this configuration, these devices 322, 323, and 324 may only communicate with each other. To communicate with other wireless communication devices within the system 300 or to communicate outside of the system 300, the devices 322, 323, and/or 324 need to affiliate with one of the base stations or access points 312 or 316.
The base stations or access points 312, 316 are located within basic service set (BSS) areas 311 and 313, respectively, and are operably coupled to the network hardware 334 via local area network connections 336, 338. Such a connection provides the base station or access point 312-316 with connectivity to other devices within the system 300 and provides connectivity to other networks via the WAN connection 342. To communicate with the wireless communication devices within its BSS 311 or 313, each of the base stations or access points 312-116 has an associated antenna or antenna array. For instance, base station or access point 312 wirelessly communicates with wireless communication devices 318 and 320 while base station or access point 316 wirelessly communicates with wireless communication devices 326—332. Typically, the wireless communication devices register with a particular base station or access point 312, 316 to receive services from the communication system 300.
Typically, base stations are used for cellular telephone systems (e.g., advanced mobile phone services (AMPS), digital AMPS, global system for mobile communications (GSM), code division multiple access (CDMA), local multi-point distribution systems (LMDS), multi-channel-multi-point distribution systems (MMDS), Enhanced Data rates for GSM Evolution (EDGE), General Packet Radio Service (GPRS), high-speed downlink packet access (HSDPA), high-speed uplink packet access (HSUPA and/or variations thereof) and like-type systems, while access points are used for in-home or in-building wireless networks (e.g., IEEE 802.11, Bluetooth, ZigBee, any other type of radio frequency based network protocol and/or variations thereof). Regardless of the particular type of communication system, each wireless communication device includes a built-in radio and/or is coupled to a radio.
As illustrated, the host device 318-332 includes a processing module 450, memory 452, a radio interface 454, an input interface 458, and an output interface 456. The processing module 450 and memory 452 execute the corresponding instructions that are typically done by the host device. For example, for a cellular telephone host device, the processing module 450 performs the corresponding communication functions in accordance with a particular cellular telephone standard.
The radio interface 454 allows data to be received from and sent to the radio 460. For data received from the radio 460 (e.g., inbound data), the radio interface 454 provides the data to the processing module 450 for further processing and/or routing to the output interface 456. The output interface 456 provides connectivity to an output display device such as a display, monitor, speakers, etc., such that the received data may be displayed. The radio interface 454 also provides data from the processing module 450 to the radio 460. The processing module 450 may receive the outbound data from an input device such as a keyboard, keypad, microphone, etc., via the input interface 458 or generate the data itself. For data received via the input interface 458, the processing module 450 may perform a corresponding host function on the data and/or route it to the radio 460 via the radio interface 454.
Radio 460 includes a host interface 462, digital receiver processing module 464, an analog-to-digital converter 466, a high pass and low pass filter module 468, an IF mixing down conversion stage 470, a receiver filter 471, a low noise amplifier 472, a transmitter/receiver switch 473, a local oscillation module 474 (which may be implemented, at least in part, using a voltage controlled oscillator (VCO)), memory 475, a digital transmitter processing module 476, a digital-to-analog converter 478, a filtering/gain module 480, an IF mixing up conversion stage 482, a power amplifier 484, a transmitter filter module 485, a channel bandwidth adjust module 487, and an antenna 486. The antenna 486 may be a single antenna that is shared by the transmit and receive paths as regulated by the Tx/Rx switch 473, or may include separate antennas for the transmit path and receive path. The antenna implementation will depend on the particular standard to which the wireless communication device is compliant.
The digital receiver processing module 464 and the digital transmitter processing module 476, in combination with operational instructions stored in memory 475, execute digital receiver functions and digital transmitter functions, respectively. The digital receiver functions include, but are not limited to, digital intermediate frequency to baseband conversion, demodulation, constellation demapping, decoding, and/or descrambling. The digital transmitter functions include, but are not limited to, scrambling, encoding, constellation mapping, modulation, and/or digital baseband to IF conversion. The digital receiver and transmitter processing modules 464 and 476 may be implemented using a shared processing device, individual processing devices, or a plurality of processing devices. Such a processing device may be a microprocessor, micro-controller, digital signal processor, microcomputer, central processing unit, field programmable gate array, programmable logic device, state machine, logic circuitry, analog circuitry, digital circuitry, and/or any device that manipulates signals (analog and/or digital) based on operational instructions. The memory 475 may be a single memory device or a plurality of memory devices. Such a memory device may be a read-only memory, random access memory, volatile memory, non-volatile memory, static memory, dynamic memory, flash memory, and/or any device that stores digital information. Note that when the processing module 464 and/or 476 implements one or more of its functions via a state machine, analog circuitry, digital circuitry, and/or logic circuitry, the memory storing the corresponding operational instructions is embedded with the circuitry comprising the state machine, analog circuitry, digital circuitry, and/or logic circuitry.
In operation, the radio 460 receives outbound data 494 from the host device via the host interface 462. The host interface 462 routes the outbound data 494 to the digital transmitter processing module 476, which processes the outbound data 494 in accordance with a particular wireless communication standard (e.g., IEEE 802.11, Bluetooth, ZigBee, WiMAX (Worldwide Interoperability for Microwave Access), any other type of radio frequency based network protocol and/or variations thereof etc.) to produce outbound baseband signals 496. The outbound baseband signals 496 will be digital base-band signals (e.g., have a zero IF) or digital low IF signals, where the low IF typically will be in the frequency range of one hundred kHz (kilo-Hertz) to a few MHz (Mega-Hertz).
The digital-to-analog converter 478 converts the outbound baseband signals 496 from the digital domain to the analog domain. The filtering/gain module 480 filters and/or adjusts the gain of the analog signals prior to providing it to the IF mixing stage 482. The IF mixing stage 482 converts the analog baseband or low IF signals into RF signals based on a transmitter local oscillation 483 provided by local oscillation module 474. The power amplifier 484 amplifies the RF signals to produce outbound RF signals 498, which are filtered by the transmitter filter module 485. The antenna 486 transmits the outbound RF signals 498 to a targeted device such as a base station, an access point and/or another wireless communication device.
The radio 460 also receives inbound RF signals 488 via the antenna 486, which were transmitted by a base station, an access point, or another wireless communication device. The antenna 486 provides the inbound RF signals 488 to the receiver filter module 471 via the Tx/Rx switch 473, where the Rx filter 471 bandpass filters the inbound RF signals 488. The Rx filter 471 provides the filtered RF signals to low noise amplifier 472, which amplifies the signals 488 to produce an amplified inbound RF signals. The low noise amplifier 472 provides the amplified inbound RF signals to the IF mixing module 470, which directly converts the amplified inbound RF signals into an inbound low IF signals or baseband signals based on a receiver local oscillation 481 provided by local oscillation module 474. The down conversion module 470 provides the inbound low IF signals or baseband signals to the filtering/gain module 468. The high pass and low pass filter module 468 filters, based on settings provided by the channel bandwidth adjust module 487, the inbound low IF signals or the inbound baseband signals to produce filtered inbound signals.
The analog-to-digital converter 466 converts the filtered inbound signals from the analog domain to the digital domain to produce inbound baseband signals 490, where the inbound baseband signals 490 will be digital base-band signals or digital low IF signals, where the low IF typically will be in the frequency range of one hundred kHz to a few MHz. The digital receiver processing module 464, based on settings provided by the channel bandwidth adjust module 487, decodes, descrambles, demaps, and/or demodulates the inbound baseband signals 490 to recapture inbound data 492 in accordance with the particular wireless communication standard being implemented by radio 460. The host interface 462 provides the recaptured inbound data 492 to the host device 318-332 via the radio interface 454.
As one of average skill in the art will appreciate, the wireless communication device of the embodiment 400 of
Any of the various embodiments of communication device that may be implemented within various communication systems can incorporate functionality to perform communication via more than one standard, protocol, or other predetermined means of communication. For example, a single communication device, designed in accordance with certain aspects of the invention, can include functionality to perform communication in accordance with a first protocol, a second protocol, and/or a third protocol, and so on. These various protocols may be WiMAX (Worldwide Interoperability for Microwave Access) protocol, a protocol that complies with a wireless local area network (WLAN/WiFi) (e.g., one of the IEEE (Institute of Electrical and Electronics Engineer) 802.11 protocols such as 802.11a, 802.11b, 802.11g, 802.11n, 802.11ac, etc.), a Bluetooth protocol, or any other predetermined means by which wireless communication may be effectuated.
As illustrated, the host device 318-332 includes a processing module 550, memory 552, radio interface 554, input interface 558 and output interface 556. The processing module 550 and memory 552 execute the corresponding instructions that are typically done by the host device. For example, for a cellular telephone host device, the processing module 550 performs the corresponding communication functions in accordance with a particular cellular telephone standard.
The radio interface 554 allows data to be received from and sent to the radio 560. For data received from the radio 560 (e.g., inbound data), the radio interface 554 provides the data to the processing module 550 for further processing and/or routing to the output interface 556. The output interface 556 provides connectivity to an output display device such as a display, monitor, speakers, et cetera such that the received data may be displayed. The radio interface 554 also provides data from the processing module 550 to the radio 560. The processing module 550 may receive the outbound data from an input device such as a keyboard, keypad, microphone, et cetera via the input interface 558 or generate the data itself. For data received via the input interface 558, the processing module 550 may perform a corresponding host function on the data and/or route it to the radio 560 via the radio interface 554.
Radio 560 includes a host interface 562, a baseband processing module 564, memory 566, a plurality of radio frequency (RF) transmitters 568-372, a transmit/receive (T/R) module 574, a plurality of antennae 582-386, a plurality of RF receivers 576-380, and a local oscillation module 5100 (which may be implemented, at least in part, using a VCO). The baseband processing module 564, in combination with operational instructions stored in memory 566, execute digital receiver functions and digital transmitter functions, respectively. The digital receiver functions, include, but are not limited to, digital intermediate frequency to baseband conversion, demodulation, constellation demapping, decoding, de-interleaving, fast Fourier transform, cyclic prefix removal, space and time decoding, and/or descrambling. The digital transmitter functions, include, but are not limited to, scrambling, encoding, interleaving, constellation mapping, modulation, inverse fast Fourier transform, cyclic prefix addition, space and time encoding, and/or digital baseband to IF conversion. The baseband processing modules 564 may be implemented using one or more processing devices. Such a processing device may be a microprocessor, micro-controller, digital signal processor, microcomputer, central processing unit, field programmable gate array, programmable logic device, state machine, logic circuitry, analog circuitry, digital circuitry, and/or any device that manipulates signals (analog and/or digital) based on operational instructions. The memory 566 may be a single memory device or a plurality of memory devices. Such a memory device may be a read-only memory, random access memory, volatile memory, non-volatile memory, static memory, dynamic memory, flash memory, and/or any device that stores digital information. Note that when the processing module 564 implements one or more of its functions via a state machine, analog circuitry, digital circuitry, and/or logic circuitry, the memory storing the corresponding operational instructions is embedded with the circuitry comprising the state machine, analog circuitry, digital circuitry, and/or logic circuitry.
In operation, the radio 560 receives outbound data 588 from the host device via the host interface 562. The baseband processing module 564 receives the outbound data 588 and, based on a mode selection signal 5102, produces one or more outbound symbol streams 590. The mode selection signal 5102 will indicate a particular mode as are illustrated in the mode selection tables, which appear at the end of the detailed discussion. Such operation as described herein is exemplary with respect to at least one possible embodiment, and it is of course noted that the various aspects and principles, and their equivalents, of the invention may be extended to other embodiments without departing from the scope and spirit of the invention.
For example, the mode selection signal 5102, with reference to table 1 may indicate a frequency band of 2.4 GHz or 5 GHz, a channel bandwidth of 20 or 22 MHz (e.g., channels of 20 or 22 MHz width) and a maximum bit rate of 54 megabits-per-second. In other embodiments, the channel bandwidth may extend up to 1.28 GHz or wider with supported maximum bit rates extending to 1 gigabit-per-second or greater. In this general category, the mode selection signal will further indicate a particular rate ranging from 1 megabit-per-second to 54 megabits-per-second. In addition, the mode selection signal will indicate a particular type of modulation, which includes, but is not limited to, Barker Code Modulation, BPSK, QPSK, CCK, 16 QAM and/or 64 QAM. As is further illustrated in table 1, a code rate is supplied as well as number of coded bits per subcarrier (NBPSC), coded bits per OFDM symbol (NCBPS), and data bits per OFDM symbol (NDBPS).
The mode selection signal may also indicate a particular channelization for the corresponding mode which for the information in table 1 is illustrated in table 2. As shown, table 2 includes a channel number and corresponding center frequency. The mode select signal may further indicate a power spectral density mask value which for table 1 is illustrated in table 3. The mode select signal may alternatively indicate rates within table 4 that has a 5 GHz frequency band, 20 MHz channel bandwidth and a maximum bit rate of 54 megabits-per-second. If this is the particular mode select, the channelization is illustrated in table 5. As a further alternative, the mode select signal 5102 may indicate a 2.4 GHz frequency band, 20 MHz channels and a maximum bit rate of 192 megabits-per-second as illustrated in table 6. In table 6, a number of antennae may be utilized to achieve the higher bit rates. In this instance, the mode select would further indicate the number of antennae to be utilized. Table 7 illustrates the channelization for the set-up of table 6. Table 8 illustrates yet another mode option where the frequency band is 2.4 GHz, the channel bandwidth is 20 MHz and the maximum bit rate is 192 megabits-per-second. The corresponding table 8 includes various bit rates ranging from 12 megabits-per-second to 216 megabits-per-second utilizing 2-4 antennae and a spatial time encoding rate as indicated. Table 9 illustrates the channelization for table 8. The mode select signal 102 may further indicate a particular operating mode as illustrated in table 10, which corresponds to a 5 GHz frequency band having 40 MHz frequency band having 40 MHz channels and a maximum bit rate of 486 megabits-per-second. As shown in table 10, the bit rate may range from 13.5 megabits-per-second to 486 megabits-per-second utilizing 1-4 antennae and a corresponding spatial time code rate. Table 10 further illustrates a particular modulation scheme code rate and NBPSC values. Table 11 provides the power spectral density mask for table 10 and table 12 provides the channelization for table 10.
It is of course noted that other types of channels, having different bandwidths, may be employed in other embodiments without departing from the scope and spirit of the invention. For example, various other channels such as those having 80 MHz, 120 MHz, and/or 160 MHz of bandwidth may alternatively be employed such as in accordance with IEEE Task Group ac (TGac VHTL6).
The baseband processing module 564, based on the mode selection signal 5102 produces the one or more outbound symbol streams 590 from the output data 588. For example, if the mode selection signal 5102 indicates that a single transmit antenna is being utilized for the particular mode that has been selected, the baseband processing module 564 will produce a single outbound symbol stream 590. Alternatively, if the mode select signal indicates 2, 3 or 4 antennae, the baseband processing module 564 will produce 2, 3 or 4 outbound symbol streams 590 corresponding to the number of antennae from the output data 588.
Depending on the number of outbound streams 590 produced by the baseband module 564, a corresponding number of the RF transmitters 568-372 will be enabled to convert the outbound symbol streams 590 into outbound RF signals 592. The transmit/receive module 574 receives the outbound RF signals 592 and provides each outbound RF signal to a corresponding antenna 582-386.
When the radio 560 is in the receive mode, the transmit/receive module 574 receives one or more inbound RF signals via the antennae 582-386. The T/R module 574 provides the inbound RF signals 594 to one or more RF receivers 576-380. The RF receiver 576-380 converts the inbound RF signals 594 into a corresponding number of inbound symbol streams 596. The number of inbound symbol streams 596 will correspond to the particular mode in which the data was received (recall that the mode may be any one of the modes illustrated in tables 1-12). The baseband processing module 560 receives the inbound symbol streams 590 and converts them into inbound data 598, which is provided to the host device 318-332 via the host interface 562.
In one embodiment of radio 560 it includes a transmitter and a receiver. The transmitter may include a MAC module, a PLCP module, and a PMD module. The Medium Access Control (MAC) module, which may be implemented with the processing module 564, is operably coupled to convert a MAC Service Data Unit (MSDU) into a MAC Protocol Data Unit (MPDU) in accordance with a WLAN protocol. The Physical Layer Convergence Procedure (PLCP) Module, which may be implemented in the processing module 564, is operably coupled to convert the MPDU into a PLCP Protocol Data Unit (PPDU) in accordance with the WLAN protocol. The Physical Medium Dependent (PMD) module is operably coupled to convert the PPDU into a plurality of radio frequency (RF) signals in accordance with one of a plurality of operating modes of the WLAN protocol, wherein the plurality of operating modes includes multiple input and multiple output combinations.
An embodiment of the Physical Medium Dependent (PMD) module includes an error protection module, a demultiplexing module, and a plurality of direction conversion modules. The error protection module, which may be implemented in the processing module 564, is operably coupled to restructure a PPDU (PLCP (Physical Layer Convergence Procedure) Protocol Data Unit) to reduce transmission errors producing error protected data. The demultiplexing module is operably coupled to divide the error protected data into a plurality of error protected data streams The plurality of direct conversion modules is operably coupled to convert the plurality of error protected data streams into a plurality of radio frequency (RF) signals.
It is also noted that the wireless communication device of this diagram, as well as others described herein, may be implemented using one or more integrated circuits. For example, the host device may be implemented on one integrated circuit, the baseband processing module 564 and memory 566 may be implemented on a second integrated circuit, and the remaining components of the radio 560, less the antennae 582-586, may be implemented on a third integrated circuit. As an alternate example, the radio 560 may be implemented on a single integrated circuit. As yet another example, the processing module 550 of the host device and the baseband processing module 564 may be a common processing device implemented on a single integrated circuit. Further, the memory 552 and memory 566 may be implemented on a single integrated circuit and/or on the same integrated circuit as the common processing modules of processing module 550 and the baseband processing module 564.
The previous diagrams and their associated written description illustrate some possible embodiments by which a wireless communication device may be constructed and implemented. In some embodiments, more than one radio (e.g., such as multiple instantiations of the radio 460, the radio 560, a combination thereof, or even another implementation of a radio) is implemented within a wireless communication device. For example, a single wireless communication device can include multiple radios therein to effectuate simultaneous transmission of two or more signals. Also, multiple radios within a wireless communication device can effectuate simultaneous reception of two or more signals, or transmission of one or more signals at the same time as reception of one or more other signals (e.g., simultaneous transmission/reception).
Within the various diagrams and embodiments described and depicted herein, wireless communication devices may generally be referred to as WDEVs, DEVs, TXs, and/or RXs. It is noted that such wireless communication devices may be wireless stations (STAs), access points (APs), or any other type of wireless communication device without departing from the scope and spirit of the invention. Generally speaking, wireless communication devices that are APs may be referred to as transmitting or transmitter wireless communication devices, and wireless communication devices that are STAs may be referred to as receiving or receiver wireless communication devices in certain contexts.
Of course, it is noted that the general nomenclature employed herein wherein a transmitting wireless communication device (e.g., such as being an AP, or a STA operating as an ‘AP’ with respect to other STAs) initiates communications, and/or operates as a network controller type of wireless communication device, with respect to a number of other, receiving wireless communication devices (e.g., such as being STAs), and the receiving wireless communication devices (e.g., such as being STAs) responding to and cooperating with the transmitting wireless communication device in supporting such communications.
Of course, while this general nomenclature of transmitting wireless communication device(s) and receiving wireless communication device(s) may be employed to differentiate the operations as performed by such different wireless communication devices within a communication system, all such wireless communication devices within such a communication system may of course support bi-directional communications to and from other wireless communication devices within the communication system. In other words, the various types of transmitting wireless communication device(s) and receiving wireless communication device(s) may all support bi-directional communications to and from other wireless communication devices within the communication system.
Various aspects and principles, and their equivalents, of the invention as presented herein may be adapted for use in various standards, protocols, and/or recommended practices (including those currently under development) such as those in accordance with IEEE 802.11x (e.g., where x is a, b, g, n, ac, ah, ad, af, etc.).
Within wireless communication systems or networks, certain of the wireless communication devices therein may need to perform certain calibration operations from time to time. For example, calibration operations may be performed in response to any of a variety of conditions or changes of conditions. Environmental changes such as temperature drift, changes of humidity, etc. may alter the manner by which certain electronic components within a wireless communication device respond or operate. In addition, certain temperatures (e.g., relatively high [such as 90° F. or 100° F.] or relatively low temperatures [such as 32° F. or even well below 0° F.]) may present challenges for the proper operation of electronic components within a wireless communication device. For example, with respect to such environmental changes, the operation of one or more components within a wireless communication device may drift or change as a function of time. As such, and associated calibration operation may be required. As a function of time, additional calibration operations (e.g., such as recalibration operations, refreshment calibration operations, etc.) may be performed at different subsequent times.
When a given wireless communication device performs such calibration operations, depending upon which of the one or more complements within the wireless communication device undergo calibration, interference may unfortunately be generated which will deleteriously affect the operation of other wireless communication devices within the wireless communication system. Generally speaking, certain calibration operations may spill energy onto the communication medium (e.g., the air in accordance with wireless communication systems).
One example of an electronic complement within a wireless communication device that may generate interference during calibration is that of a power amplifier (PA). As the reader will understand, any of a variety of components within a wireless communication device may also generate interference during their respective calibration operations, and/or be affected by interference incurred from operations (such as calibration) performed by other wireless communication devices.
Generally speaking, calibration of different respective components within a wireless communication device is performed to ensure acceptable an adequate operation of the wireless communication device. For example, in accordance with a number of different considerations including the relatively low-cost implementation, high precision requirements, the desire to transmit high powers for increasingly longer communication range, the challenging and time varying characteristics of the environments in which wireless communication devices operate [both in terms of the physical surroundings/environmental considerations such as thermal effects which may be introduced by other hardware components as well as challenges introduced within certain wireless communication channel conditions, such as fading channels], to ensure acceptable performance of a wireless communication device, one or more of the different component therein typically undergo calibration.
For example, considering an exemplary wireless communication system embodiment, such as that of a high-speed wireless local area network (WLAN) operating in accordance with IEEE 802.11n, the transmitter error magnitude vector (EMV), or transmit precision, typically has to be up to −28 dBr (dB relative) for the highest consolation of 64 QAM with the most aggressive code rate. To comply with such operational constraints, the residual distortion are typically must be below the useful signal power by a factor of 10(−28/10).
Moreover, depending on the particular application under consideration, there may be additional requirements with which a given wireless communication device must comply. For example, there may be relatively tight requirements for the so-called spectral mask, corresponding to the power spectrum of a signal and it's regulated limitation in regards to leakage into adjacent channels (e.g., can only leak by very small amounts, less than some threshold). For example, in accordance with the currently developing IEEE 802.11 ac standard, certain operational requirements are relatively more challenging than those provided in accordance with IEEE 802.11n standard (e.g., a relative predecessor to the currently developing IEEE 802.11ac standard). For example, in accordance with the currently developing IEEE 802.11 ac standard, the transmit EVM's is expected to be lower than −30 dBr. As the reader will understand, meeting stringent requirements such as these and others can become more difficult when the amount of transmit power [e.g., in milli-watts, or dBm] desired to be emitted from an antenna increases.
In order to ensure acceptable performance of the wireless communication device, such calibration operations of are performed for one or more of the components within a wireless communication device. Generally speaking, various techniques may be used to measure, either implicitly or explicitly, imperfections and corresponding compensation techniques may be implemented to minimize or eliminate those imperfections. Also, generally speaking, in accordance with wireless communications, many such calibration operations may be directed to components within a radio of a wireless communication device.
As may be understood, when the PA and/or other components within one of the radios of the wireless communication device 610 turns on or operates, that may introduce undesirable effects within another of the radios within wireless communication device 610. As also shown in the diagram, the respective communications associated with each of the various radios in the wireless communication device 610 may be directed to different other wireless communication devices among the wireless communication devices 650-670. Of course, in some other embodiments, a given other wireless communication device includes capability also to support communications using multiple radios therein (e.g., to support simultaneous receive-transmit (RX-TX) or transmit-transmit (TX-TX)), and in such a case, the other wireless communication device may also support simultaneous communications with the wireless communication device 610.
As may be seen with respect to this diagram, when wireless communication device 610 performs any calibration operations with respect to a PA 620a and/or any other component 630b, interference may unfortunately be generated that will affect the operation of one or more of the wireless communication devices 650-670. For example, any such energy that may be spilled onto the communication medium from the PA 620a may deleteriously affect a calibration operation that may be performed by one or more of the wireless communication devices 650-670. In some embodiments, the wireless communication device 610 may include more than one radio. Each respective additional radio that may be included within the wireless communication device 610 may also include a respective power amplifier and/or any other component. Analogously, when wireless communication device 610 performs any calibration operations with respect to a PA 630a and/or any other component 630b, interference may unfortunately be generated that will deleteriously affect the operation of one or more of the wireless communication devices 650-670 (e.g., such as a corresponding calibration operation performed thereby). Generally speaking, those wireless communication devices which may be in relatively closer proximity to a wireless communication device that is performing one or more calibration operations may be affected more significantly than those wireless communication devices which are relatively further away from the calibrating wireless communication device.
With respect to calibration operations which may be performed with respect to a power amplifier (PA), certain wireless communication devices can include a highly accurate external power amplifier designed for the last stage of the analog (radio) transmit chain. In other embodiments, such as relatively low-cost applications, internal or on-chip PAs may be implemented in the same construct (e.g., the same CMOS technology) as other relatively lower power component of the transmitter or receiver chains. In some instances, such internal or on-chip PAs are implemented within the same chip as these other components; and in other instances, they are implemented within separate chips that may be connected via one or more buses, interconnects, etc. For such internal or on-chip PA designs, pre-distortion calibration (which may be referred to as PA PD calibration) techniques may be employed to linearize the effective characteristic of an internal PA so that it assists in the transmission of high-power, high precision signals from a wireless communication device.
For some examples as described herein with respect to implementation of one or more PAs, as can be seen with respect to the embodiment shown in
In one type of PA PD calibration, special test signals are transmitted from a digital transmitter to an analog transmitter all the way to, and through, the internal or on-chip PA. A feedback or loopback mechanism may be used to probe the transmit signal at the PA output and route it back into the receiver. Then, one or more digital correlation techniques may be used to determine the relative degree of distortion. Dependent upon this distortion and its relative degree, one or more compensation settings may be subsequently determined to minimize or eliminate such PA distortion when the radio transmitter is later used for actual data transmissions.
It is noted that such a PAPD calibration, since the PA itself is involved in the process of calibration and the PA is implemented within the last stage of the analog (radio) transmit chain and is often times directly connected to the antenna (or indirectly connected such that one or more intervening component such as a filter module, switch module, etc. is implemented in between the PA and antenna), the test signal will be radiated from the antenna. This means that the spectral channel in which the wireless communication system resides and performs its calibration will not be available for use for other communications. For example, considering the spectral channel such as 5240 MHz or 2412 MHz and a given surrounding signal bandwidth, such as including guard intervals, etc., such frequency spectra will not be available for use in other communications during calibration operations associated therewith. Such a calibration operation that spills energy onto the communication medium (e.g., onto the air in the context of wireless communications) may generally be referred to as a loud calibration operation. That is to say, detectable energy may be spilled onto the communication medium during such a calibration operation that is loud.
It is also noted that certain calibration operations, while being loud, may or may not be requires-silence calibration operations. For example, a given PAPD calibration may, or may not be a requires-silence calibration operation. For example, as described further above, a transmit signal coming out of a PA during PAPD calibration is looped back into the receiver of the very same wireless communication device. As the reader will understand, any other signal energy that may be impinging at the very same time onto the antenna of this same wireless communication device, such as may be emitted from one or more other wireless communication devices on the same channel, may also be coupled into the receiver of that very same wireless communication device thereby adding to the calibration test signal. As may be understood, such additional information may unfortunately skew the calibration operation itself. Such ingress energies, if strong enough, may add to the calibration signal to such a degree as to affect negatively the outcome of the calibration operation. Also, it is noted that during such calibration operations, the digital and analog transmit chains are busy/operational for the calibration operation itself, so typical data transmissions cannot occur.
As also mentioned elsewhere herein, while certain of the components been a wireless communication device, such as a PA, may undergo calibration, any other component therein may also undergo calibration from time to time. Aside from PAPD calibration, there are also other calibration types. For example, one calibration type that is used to calibrate both radio transmitters as well as radio receivers is quadrature calibration, oftentimes referred to as I/Q calibration. In many wireless communication systems, a radio frequency (RF) signal [e.g., such as in the multi-gigahertz frequency spectrum] is often times represented by two respective signals in the so-called signal baseband, namely the in phase signal (I-signal) and the quadrature phase signal (Q-signal). Considered together, the I-signal and Q-signal allow representation of any RF signal of the desired phase in magnitude.
In the situation in which the capital I and Q signals are out of balance in the radio (such as may be referred to as I/Q imbalance), there may unfortunately be signal integrity degradation which can result in communication performance loss for both transmissions and receptions. Such I/Q imbalance is prevalent in many modern wireless communication devices, and appropriate calibration techniques are employed to minimize the deleterious effects associated therewith.
In accordance with transmit I/Q calibration, a test signal may be transmitted in loopback to the receiver (e.g., such as described above with respect to another embodiment) to compute compensation settings so that future data transmissions generate a clean signal. As the I/Q imbalance characteristics may often be measured without the PA of the wireless communication device being enabled, very little, if any, signal energy may be spilled from the antenna onto the communication medium during the calibration operation. As such, a calibration operation, such as the transmit I/Q calibration operation, may be referred to as a silent calibration. That is to say, a silent calibration may generally be referred to as one in which little or no signal energy is spilled from the intent onto the communication medium during the respective calibration operation.
Analogously, receive I/Q calibration is often implemented as a silent calibration operation such that the transmit circuitry relatively close to the antenna, such as including the PA, is not necessarily needed to measure the I/Q imbalance and may subsequently be turned off during such a respective calibration operation.
It is noted that there are many other calibration operations that may be performed within a wireless communication device that are silent calibration operations. Generally speaking, many calibration operations that are performed within a wireless communication device, such as those related to voltage controlled oscillator (VCO) calibration, resistance-capacitance (RC) calibration, etc., are in fact silent calibration operations.
In addition, it is noted that most calibration operations are also requires-silence calibration operations. That is to say, during such a requires-silence calibration operation, it is often times imperative that no other relatively strong signal is radiating energy into the antenna in the frequency channel on which the wireless communication device is operating. As may be understood, this is due the fact that characterizing the radio behavior may be very sensitive to such additive ingress signals that may lead to incorrect readings thereby causing the radio characteristic to be misinterpreted thereby skewing the associated calibration operation (e.g., the calibration operation would then calibrate based upon improper readings).
Generally speaking, certain calibration operations are performed to ensure acceptable performance of the wireless communication device. From certain perspectives, such calibration operations may be viewed as “cleaning up” one or more components of the wireless communication device from time to time. Often times, such calibration operations are performed off-line in the sense that a given wireless communication device is put into a special operational mode, and the behavior of one or more components is measured and associated compensation settings are derived there from. As may be understood, regular communications and traffic activity is then interrupted for a period of time in which the calibration operation is to take place. The time period during which such one or more calibration operations may be performed may generally be referred to as a calibration interval.
Also, with respect to the characterization of different types of calibration operations, there are loud calibrations and silent calibrations. With respect to a loud calibration, a signal is present and detectable by other wireless communication devices on the same frequency channel. During such a loud calibration, no communication activity will typically be possible within that given frequency channel, as the communication medium is blocked by the calibration signal being spilled out onto the communication medium from the antenna (e.g., spilled onto the air from the antenna in the context of wireless communications).
In contrast, during a silent calibration, no meaningful amount of energy is spilled out onto the communication medium from the antenna, so that communication channel quality will not be deleteriously affected by the ongoing calibration. Nevertheless, even during a silent calibration operation, no other signal activity should typically be happening on that given frequency channel, as many calibration operations are inherently requires-silence calibrations, as described elsewhere herein. That is to say, even though a given calibration operation may in fact be a silent calibration operation, in which no meaningful amount of energy is spilled out onto the communication medium, such a given calibration operation may also be a requires-silence calibration operation; as such, no other signal activity should be performed during that respective calibration interval.
With respect to requires-silence calibration operations, it is noted that no other wireless communication device within the vicinity of the wireless communication device performing such a requires-silence calibration operation should be transmitting a signal or spilling energy onto the communication medium (e.g., should not be performing a loud calibration, any regular data packet transmissions, etc.) As such external ingress signals may unfortunately coupling to the receive circuitry thereby adding to any existence calibration test signal (which can lead to failure of the calibration operation itself).
However, there are certain calibration operations that are does-not-require-silence calibration operations, in that, such a requires-silence calibration operation may be performed even in the event that another wireless communication device is in fact transmitting a signal or spilling energy onto the communication medium. Generally speaking, various calibration operations may be characterized as a loud calibration operation or a silent calibration operation. Also, various calibration operations may be characterized as being a requires-silence calibration operation or a does-not-require-silence calibration operation. Any combination of these various categorizations of calibration operations may be used to characterize a given calibration operation. For example, a given calibration operation may be loud and requires-silence calibration operation, a loud and does-not-require-silence calibration operation, a silent and requires-silence calibration operation, or a silent and does-not-require-silence calibration operation.
Moreover, it is noted that certain calibration operations may be performed more than once. For example, such calibration operations may be performed periodically over time. Any of a number of various criteria may be used as a triggering event to initiate a calibration operation. For example, as you of changes in operating conditions may precipitate or trigger a calibration operation, many of which have been described above and elsewhere herein.
As may be understood with respect to certain calibration operations as may be performed by various wireless communication devices within a wireless communication system, certain of those calibration operations make the communication medium unavailable for use for normal data packet transmissions. In certain wireless communication system applications, such interruption of access to the communication medium can be problematic. For example, with respect to video signaling over wireless communication links, relatively small latencies are preferable. Certain wireless gaming systems, and other interactive type applications, are also relatively more susceptible to such interaction access to the communication medium and also operate better with relatively small latencies. Generally speaking, with respect to a given communication link, any delays in the end-to-end communication chain are undesirable. In the context of video signaling over wireless communication links, such interruptions may result in degradation to video quality. In context of interactive applications, such as gaming systems, such interruptions may result in relatively slow response times thereby degrading the user experience.
For example, data packet gets stalled or delayed for a relatively long time in the communication channel, the flow of data packets might be easily interrupted. Again, in the context of video signaling, there may unfortunately be a very noticeable video quality degradation for a given period of time until the channel quality recovers.
As may be understood in accordance with the teachings herein, certain calibration operations may unfortunately conflict with a requirement to have relatively low delay (e.g., low latency) and a relatively high quality of service within certain wireless communication systems (e.g., such as video signaling, interactive applications such as gaming, etc.). In certain embodiments, such calibration operations (e.g., such as those corresponding to one or more radio component within a wireless communication device) may take place will require a time period of over several milliseconds, or sometimes tens of milliseconds, to complete. However, certain application environments, such as those including video signaling, may perform more optimally with a data latency as low as approximately 5 to 10 ms. Herein, various aspects, and their equivalents, of the invention may be employed to minimize the impact of one or more calibration operations on the consistency and latency of data traffic within a communication system. Again, certain applications are inherently sensitive to the interruption of data packets therein (e.g., such as video signaling, interactive applications such as gaming, etc.), and such deleterious effects may be minimized or eliminated using the various teachings herein.
Analogously, other wireless communication devices within a wireless communication system may have similar structure, architecture, component, etc. For example, wireless communication device 702 may include a power amplifier (PA) 702a and one or more other components 702b.
When the wireless communication device 701 performs one or more calibration operations, interference may unfortunately be emitted over the air and create interference that may deleteriously affect the operation of other wireless communication devices (e.g., such as one or more calibration operations performed by those other wireless communication devices). For example, the wireless communication device 702 may unfortunately be affected by interference generated by the wireless communication device 701 during one or more calibration operations performed thereby.
As described elsewhere herein, calibration may be performed in accordance with any of a variety of manners and in response to any a variety of considerations. Calibration operations may be performed periodically, in response to changes in temperature, humidity, environmental conditions, etc.
Also, while many of the diagrams and embodiments described herein are directed particularly towards wireless communication devices operative within wireless communication systems, it is noted that such operations and functionality as described herein may also be implemented within communication devices operative it within other types of communication systems as well (e.g., wired communication systems, fiber-optic communication systems, etc. and/or any combination thereof). That is to say, certain communication systems are implemented as being a combination of more than one communication system type and different respective communication the links therein may be implemented using different forms of communication media (e.g., some being wireless, some being wired, some being fiber-optic, etc. and/or any combination thereof). Generally speaking, any communication device operative within any one or more types of communication systems may be implemented to support such operations and functionality as described herein.
With respect to a CTS2SELF type calibration announcement frame, it is noted that a CTS or clear to send communication is a response to a request to send (RTS). Herein, a CTS is sent with an address of the given device performing the transmission, hence the name CTS2SELF. The use of such a CTS2SELF type calibration announcement frame is one possible embodiment by which calibration operations may be better coordinated and organized within a wireless communication system. Of course, a variety of other types of calibration announcement frames may be employed as well.
In another embodiment, the calibration announcement frame is a broadcast packet. In even other embodiments, the calibration announcement frame is associated with a beacon. Generally speaking, any of a variety of different types of calibration announcement frames (e.g., a CTS2SELF communication, a broadcast communication, a beacon, management frame, a control packet, etc.) may be employed to inform at least one other wireless communication device of an upcoming calibration interval.
Generally speaking, within this diagram and embodiment as well as within any other diagram or embodiment herein, such a calibration announcement frame may be any desired communication provided from one of the wireless communication devices to inform other of the wireless communication devices of an upcoming calibration interval. Certain perspectives, such a calibration announcement frame is effective to inform other wireless communication devices of an upcoming calibration interval as well as to provide for, sometimes, reserving the communication medium during that calibration interval as well.
In certain embodiments, the calibration announcement frame may also include certain information and/or indicia therein describing an upcoming calibration event to be performed by the wireless communication device that provides the calibration announcement frame. For example, such information and/or indicia within the calibration announcement frame may indicate whether or not a calibration operation to be performed within the upcoming calibration events may potentially provide energy spillage onto the communication medium. If so, certain of the other wireless communication devices may take certain actions based thereon. Also, coordination/synchronization is provided for various calibration operations as may be performed by various wireless communication devices. In addition, certain operations operate by informing one or more higher layers of an upcoming calibration interval, above the physical layer (PHY), so that these one or more higher layers may take appropriate actions based upon such information.
It is noted that certain implementations of calibration announcement frames will lend themselves to and be amenable to different functions. For example, a calibration announcement frame implemented as a CTS2SELF communication typically is implemented without having a separately provisioned ‘data’ field therein. As such, a CTS2SELF communication implemented as a calibration announcement frame may be limited in some respects, in that, additional information may not be able to be provided thereby.
It is noted that when given calibration announcement frames are provided in accordance with some time domain synchronized system, such as in accordance with beaconing, the duration of the upcoming event as indicated by the calibration announcement frame may correspond to the timing structure of the time domain synchronized system. For example, when provided in accordance with beaconing, such beacons will typically be provided according to some timing structure. The duration of an upcoming event as indicated by a calibration announcement frame may be particularly constructed to correspond to the timing structure of the beaconing system (e.g., an upcoming calibration interval may be an integer multiple of the beaconing period, including his few as one beaconing period).
Also, it is noted that certain wireless communication devices include capability and functionality to support wireless communications in accordance with two or more communication standards, protocols, recommended practices, etc. For example, a given wireless communication device may include capability and functionality to support wireless communications in accordance with both IEEE 802.11x (e.g., where x is a, b, g, n, ac, ah, ad, af, etc.) as well as Bluetooth®. Of course, capability and functionality corresponding to any combination of two or more different communication standards, protocols, recommended practices, etc. may similarly be included within a given wireless communication device. In such instances, such a calibration announcement frame may be provided successively in accordance with each of those two or more different communication standards, protocols, recommended practices, etc. (e.g., firstly in accordance with a first standard, secondly in accordance with a second standard, etc.).
Each respective one of the wireless communication devices 802-806 receiving the calibration announcement frame may perform a variety of operations in response to the calibration announcement frame. In one embodiment, each of the respective wireless communication devices 802-806 will stay off of the communication medium for a particular period of time (e.g., such as may be indicated within the calibration announcement frame).
In another embodiment, each of the respective wireless communication devices 802-806 will enter a relatively more robust operational state in response to the calibration announcement frame. For example, by entering into such a relatively more robust operational state, a given wireless communication device will be less susceptible to interference that may be generated by the one or more calibration operations performed by the wireless communication device 801. A relatively more operational state may correspond preemptively to powering down certain component which may be more susceptible to interference that may be generated by the one or more calibration operations performed by the wireless communication device 801.
In even other embodiments, each of the respective wireless communication devices 802-806 may respectively analyze certain characteristics of the calibration announcement frame to determine one or more properties thereof. For example, in certain instances, the calibration announced frame will indicate an upcoming calibration interval. The wireless communication device 801 may perform one or more calibration operations during the upcoming calibration interval. However, in some situations, the wireless communication device 801 will not perform any calibration operations during the upcoming calibration interval.
Each respective wireless communication device 802-806 may analyze the calibration announcement frame, and when it is determined that the wireless communication device 801 will perform at least one calibration operation during the upcoming calibration interval, these wireless communication devices 802-806 may further identify one or more indicia within the calibration announcement frame indicating a type of at least one calibration operation to be performed by the wireless communication device 801. For example, among the various types of calibration operations, they may be generally categorized as being loud calibration operations or silent calibration operations. Furthermore, a given calibration operation may be further categorized as being a requires-silence calibration operation or a does-not-require-silence calibration operation. It is noted that a given calibration operation may be any combination of these various types, such as a loud/requires-silence calibration operation, a loud/does-not-require-silence calibration operation, a silent/does-not-require-silence calibration operation, or a silent/does-not-require-silence calibration operation.
In addition, each respective wireless communication device 802-806 may further analyze one or more local criteria for adaptively making determination of whether to perform a given calibration operation during at least a portion of the upcoming calibration interval that is indicated within the calibration announcement frame.
From certain perspectives, a calibration announcement frame may be viewed as providing for communication channel reservation for a particular period of time during which the wireless communication device transmitting the calibration announcement frame intends to perform its respective calibration. In certain situations, period of time during which such calibration operations is to be performed may exceed an acceptable latency tolerance within the wireless communication system, within one or more of the wireless communication devices, and/or a particular signaling being effectuated between two respective wireless communication devices. For example, in the context of media signaling between two respective wireless communication devices, the channel reservation for such calibration operations, as indicated by a calibration announcement frame, may unfortunately interfere with such media signaling. That is to say, given that one or more of the wireless communication devices needs to perform a calibration operation, the link quality within the communication system will therefore be affected during the calibration interval in which the one or more calibration operations are performed.
As such, one or more error recovery mechanisms (e.g., operations) may be implemented to accommodate such situations. From certain perspectives, such error recovery mechanisms may be viewed as being preemptive in view of expected problems, interference, etc. that may occur based upon future operations associated with a calibration announcement frame. In the event that the channel reservation as indicated within the calibration announcement frame exceeds acceptable latency tolerance, a given wireless communication device may, upon receipt of a calibration announcement frame (or upon an impending transmission of a calibration announcement frame there from), instruct a decoder to replay a recent portion of the media signaling (e.g., relatively recent one or more scenes). Analogously, an encoder may generate and I-frame to be provided upon the completion of the period of time associated with the calibration operations has indicated within the calibration announcement frame. As can be seen, one or more error recovery mechanisms may be employed to accommodate situations in which calibration announcement frames, and their respective associated calibration operations, may unfortunately interfere with ongoing communications between various wireless communication devices within the wireless communication system.
From certain perspectives, a communication device may be viewed as including a physical layer (PHY) and one or more higher layers, such as media access control (MAC) layer, application layer, etc. Based upon receipt of a calibration announcement frame, one or more higher layers above the physical layer (PHY) may be informed of an upcoming calibration interval as indicated within the calibration announcement frame. One or more of these higher layers may adaptively determine whether or not to perform a certain operation during the upcoming calibration interval. This cross layer communication between the physical layer in the upper layers may be implemented within the very wireless communication device that transmits the calibration announcement frame, or within a wireless communication device that receives the calibration announcement frame. That is to say, information corresponding to an upcoming calibration interval may be communicated upward to a higher layer within a given communication device.
Also, while many of the diagrams and embodiments described herein are directed towards one communication device indicating to other communication devices of such an upcoming event via a calibration announcement frame, it is noted that different layers (e.g., such as with reference to different layers of a protocol stack) may be informed of the upcoming event by the calibration announcement frame. For example, an application layer of a communication device may be informed of the upcoming event via the calibration announcement frame. As such, operation of different respective components, modules, circuitries, etc. within a given communication device may be coordinated based upon the calibration announcement frame. For example, in one instance, such a calibration announcement frame may be generated at the physical layer level (PHY) and be provided to inform higher layers within that same communication device of the upcoming event (perhaps in addition to being provided to other communication devices as well). If desired, some of those higher layers within that same communication device may perform operations that will reduce their respective sensitivity to the upcoming event. Also, if desired, some of those higher layers with the missing communication device may reschedule or modify currently scheduled operations in view of the upcoming event.
With respect to cross layer informing of an upcoming calibration interval, such as from the physical layer (PHY) level to at least one higher layer level, one or more operations may be based upon that provided information. For example, in the context of video communication systems, an application layer may suspend generating new data traffic until the calibration interval has completed. For example, given that the communication medium may not be usable during the upcoming calibration interval, preemptive action as taken by the application layer may present transmit queue congestion. Also, with respect to video decoding within a wireless communication device, a higher layer may be informed of the upcoming calibration interval, and based thereon, a video decoder may then expect to be missing one or more video packets for the duration of some or all of the upcoming calibration interval. In response to such information provided from the physical (PHY) layer, a video decoder may preemptively transition into certain techniques such as a video error concealment operational mode. In such an operational mode, one or more previous video images or segments may be repeated during the calibration interval to conceal or hide the temporary loss/interruption of the communication link during the associated calibration operation.
At the end of such a calibration interval, the video encoder, being aware of when the calibration intervals has completed, can use targeted video encoding techniques to get the video data flow back on track. For example, as mentioned above and elsewhere herein, one or more video I-frames (e.g., full video refreshment frames) may be employed in contrast to temporarily incremental frames, such as P-frames, to resynchronize a communication link that has been temporarily lost during the corresponding calibration operation. As such, a transmitter's application layer may therefore beneficially use such I-frames in response to a given calibration interval.
Also, such a calibration announcement frame may further indicate a particular degree of the upcoming event. For example, certain calibration operations may provide interference (e.g., spillage of energy onto the communication medium) that may affect other communication devices in a degree that is much higher than other calibration operations. In one embodiment, a calibration announcement frame may indicate that the upcoming event is one of at least two different types of events, namely, a silent event that will not interfere with the other communication devices or a loud event that will affect or disturb the other communication devices. Of course, it is noted that further granularity may be provided within the calibration announcement frame to indicate a particular degree to which such an upcoming event may interfere with the other communication devices.
Based upon the calibration announcement frame, certain of the wireless communication devices 902-906 selectively perform one or more calibration operations. It is noted that all of the wireless communication devices 902-906 need not necessarily perform calibration based upon or in response to receipt of the calibration announcement frame. That is to say, each respective one of the wireless communication device is 902-906 may make the particular decision of whether to perform one or more calibration operations by considering the calibration announcement frame and/or one or more local considerations. For example, each respective one of the wireless communication devices 902-906 may consider its particular history in regards to prior calibration operations. If a given wireless communication device has performed a calibration operation within a particular period of time (e.g., within X seconds), and if it is determined that another calibration operation does not need to be performed at the present time, then such a given wireless communication device need not perform a calibration operation even if afforded the opportunity to do so by the calibration announcement frame. Other local considerations may also be employed to make decisions of whether or not to perform a calibration operation. For example, temperature drift, changes of humidity, absolute temperature, processing history such as historical trends of CPU usage and/or physical memory usage, and/or any other characteristics, operational parameters, etc. may be employed in decision-making regarding whether or not to perform one or more calibration operations.
Alternatively, in response to and based on the calibration announcement frame, a given wireless communication device may selectively power down, enter a power saving and/or low power state, perform non-calibration related maintenance, etc. That is to say, in one embodiment, in response to and based on the calibration announcement frame, a given wireless communication device may perform certain operations to lessen its susceptibility to interference as may be generated during calibration by the calibration announcement frame sending wireless communication device. In another embodiment, in response to and based on the calibration announcement frame, a given wireless communication device may also perform one or more calibration operations. In yet another embodiment, in response to them based on the calibration announcement frame, a given wireless communication device may perform certain non-calibration related operations.
In addition, in an embodiment in which the calibration announcement frame provides further indication of a degree to which the upcoming event may spill energy onto the communication medium thereby potentially affecting the operation of the other communication devices, each respective communication device may consider such information in deciding which actions to take. That is to say, in addition to the consideration of a received calibration frame, additional information is extracted from that received calibration frame to assist further in the particular actions that a given communication device will take based thereon.
For example, as described elsewhere herein, a calibration announcement frame may indicate whether or not the upcoming event will still energy onto the communication medium thereby affecting the operation of other communication devices or not (e.g., such as in accordance with being a silent or loud upcoming event or calibration operation). In a situation in which the upcoming event is silent, in which additional interference will not be spilled onto the communication medium and affect the operation of the other communication devices, a given communication device may decide that it can perform other operations during the time associated with that upcoming event. For example, a given communication device may decide to perform transmission during that upcoming available time period in which the communication device that provided the calibration announcement frame will in fact be performing its silent related operations. Alternatively, if a calibration announcement frame indicates that the upcoming event could in fact still energy under the communication medium and affect operation of the communication device, a given communication device may decide to perform such operations to minimize its respective sensitivity to those upcoming operations.
Also, in situations in which further granularity is provided to indicate a relative degree to which the upcoming event may potentially affect operation of the other communication devices, a given communication device may selectively perform operations such that some, though perhaps not all, of the components therein are placed in an operational state that is relatively less susceptible to such interference associated with the upcoming event. However, there may be other components within that communication device that will not be as adversely affected by the upcoming event. That is to say, individual respective component within a given device may be selectively and independently managed based upon information related to the relative degree of potential interference that may be incurred from the upcoming event.
From certain perspectives, it can be seen that the use of a calibration announcement frame indicating an upcoming calibration interval for use in synchronizing one or more calibration operations. In one embodiment, such synchronization may be effectuated by reserving the communication medium, or airtime, by having respective wireless communication devices carry out separate and respective silent calibration operations simultaneously. For example in the case of silent calibration operations, typically no wireless communication device in the network (or out of network wireless communication devices operating within the same frequency spectrum/spectra or channel(s)) should be transmitting packets during the calibration interval. This is because such transmissions will likely deleteriously affect the calibration operations of other wireless communication devices, especially those of the requires-silence calibration operation type. In certain, a majority of the calibration operations are of the requires-silence calibration operation type.
Moreover, when certain calibration operations cannot be avoided, such as because of drift of radio characteristics within a wireless communication device over time, a flow of the data traffic (e.g., such as video data traffic) may have already been caused. For example, if an interruption from a given calibration operation is sufficiently long, one or more video frames may already be lost due to the delay introduced by the calibration operation (e.g., considering video content corresponding to one image on the screen, such as one video frame such as 1/60 seconds in many cases). In such an event, a video loss event may even be exploited to perform calibration of other wireless communication devices while the loss event is occurring and before recovery of that video stream is underway or completed.
In accordance with the calibration schedule detected within this diagram, the wireless communication device 1001 may perform calibration at or during a second time during which the other wireless communication devices 1002-1004 stay off of the communication medium (e.g., air). The wireless communication device 1001 then stays off of the communication medium (e.g., air) for the remainder of the calibration schedule to allow the other wireless communication devices 1002-1004 the opportunity to perform one or more calibration operations. For example, the wireless communication device 1002 may perform calibration at or during a third time during which the other wireless communication devices 1001 and up to 1004 stay off of the communication medium (e.g., air). Then, the wireless communication device 1002 may perform calibration at or during a fourth time during which the other wireless communication devices 1001 and up to 1003 stay off of the communication medium (e.g., air).
The calibration schedule as may be included within a calibration announcement frame may include respective periods of time (e.g., ΔTi, where each i corresponds to a given one of the devices 1002a-1002c) that may be allocated for different wireless communication devices 1001-1004 to perform their respective calibration operations. It is noted that the respective periods of time need not necessarily be equal for each of the respective wireless communication devices 1001-1004. As may be understood with respect to this diagram, each respective wireless communication device may be afforded a respective period of time during which to perform calibration.
During a given period of time assigned to a given wireless communication device, that corresponding wireless communication device may perform calibration and/or other maintenance operations. As may be understood with respect to this diagram, by having the respective wireless communication devices perform such operations at different respective times, there is a much lower likelihood that any one given wireless communication device will deleteriously affect or interfere with other wireless communication devices during its respective calibration and/or maintenance operations. For example, by temporally spacing out the respective calibration operations is performed by different wireless communication devices, reasonable assurance can be made that the calibration operations performed by any given one wireless communication device will not affect calibration operations performed by any other wireless communication devices.
As may be understood with respect to synchronize calibration as performed in accordance with in accordance with various aspects, and their equivalents, of the invention, a communication may be provided from one wireless communication device to indicate to other wireless communication devices that it is going to perform one or more calibration operations. In some embodiments, the informing that is provided to the other wireless communication devices may serve as a trigger by which those other wireless communication devices may also perform their respective one or more calibration operations. That is to say, such a communication (e.g., a calibration announcement frame) may serve as the trigger to provide the opportunity for the other wireless communication devices to perform one or more calibration operations and/or one or more non-calibration/maintenance operations. In certain situations, one or more of the other wireless communication devices performs such operations at the same time as the one wireless communication device performs its respective one or more calibration operations. Such an embodiment may generally be referred to as a group calibration implementation in which multiple of the wireless communication devices perform respective operations in parallel with one another and/or simultaneously with one another.
With respect to instances in which a calibration announcement frame provides additional information, such as with respect to a group calibration event as described above, the calibration announcement frame may include additional information to specify which particular operations may be respectively performed by the respective wireless communication devices (or by a subset thereof) in parallel with one another and/or simultaneously. That is to say, additional information may be provided within a calibration announcement frame to specify particularly those operations which one or more of the wireless communication devices may perform in accordance with the group calibration event.
In some instances, each of the other wireless communication devices need not necessarily perform a calibration operation. In some instances, a given wireless communication device has already performed a calibration operation within recent history.
In other embodiments, when a communication (e.g., a calibration announcement frame) may be provided from one wireless communication device to other wireless communication devices, one or more of those other wireless communication devices may perform certain operations (e.g., such as in accordance with allotted time associated with a maintenance window) such as entering a more robust operational state as to reduce any susceptibility to interference that may be generated when the one wireless communication device performs it's one or more calibration operations. For example, one or more of those other wireless communication devices may enter a power saving state, a power down or cool down state, or some other operational mode that provides robustness against interference.
Also, with respect to embodiments employing the communication of one or more maintenance windows, it is noted that certain implementations may be a bit challenging if all of the wireless communication devices within the wireless communication system do not have the capability to receive calibration announcement frames. For example, certain of the wireless communication devices may be out of range of other of the wireless communication devices, and may not properly received such calibration announcement frames, and thereby not be properly informed of an upcoming event (e.g., such as a maintenance window). If desired in such situations, synchronization calibration could be implemented by giving an option to certain of the wireless communication devices within the basic service set (BSS) to perform calibration if they so desire.
In addition, the local decision-making of a given wireless communication device in response to a received calibration announcement frame may be a threshold based. For example, if that given wireless communication device has performed a calibration operation within a relatively recent period of time (e.g., such as determined in comparing to some time or duration threshold), than that given wireless communication device need not necessarily perform a calibration operation even though it is provided the opportunity to do so based upon the calibration announcement frame. Moreover, other threshold based considerations may be made such as comparing operational parameters such as temperature drift, changes of humidity, absolute temperature, processing history such as historical trends of CPU usage and/or physical memory usage, and/or any other characteristics, operational parameters, etc. to one or more respective thresholds. That is to say, each respective operational parameter may have an associated threshold with which comparison is made in determining whether or not to perform certain operations in response to a received calibration announcement frame. It is also noted that certain considerations may be weighted more than others as desired within various embodiments.
As described elsewhere herein, it can be seen that a calibration announcement frame can specify whether or not the wireless communication device providing the calibration announcement frame intends to perform one or more calibration operations within an upcoming calibration interval. In addition, when one or more calibration operations are to be performed, certain embodiments of the calibration announcement frame may further specify whether or not those one or more calibration operations correspond to loud calibration or silent calibration. In even other embodiments, further granularity is provided to specify whether or not those one or more calibration operations correspond to requires-silent calibration or does-not-require-silence calibration. That is to say, a given embodiment of a calibration announcement frame made include a variety of different types of information.
A wireless communication device that receives a calibration announcement frame may perform analysis thereof to determine whether or not that wireless communication device is eligible also to perform a respective calibration operation and/or other operation (e.g., such as in accordance with certain maintenance operations). In certain embodiments, coordination is made between different wireless communication devices receiving the calibration announcement frame. For example, if a loud calibration operation is indicated within a calibration announcement frame, then a wireless communication device receiving that calibration announcement frame may simply suspend any activities; alternatively, the wireless communication device receiving that calibration announcement frame may perform a silent calibration that is also a does-not-require-silence calibration (e.g., to provide for best use of the available time corresponding to an upcoming calibration interval).
Alternatively, if a silent and requires-silence calibration operation is indicated within a calibration announcement frame, those wireless communication devices receiving that calibration announcement frame may perform their own respective silent and requires-silence calibration operations (e.g., such as may be compatible with the calibration announcement frame). Generally speaking, any compatible combination between a calibration announcement frame and various types of subsequent calibration procedures performed by one or more wireless communication devices may be employed.
Again, it is noted that any given embodiment of a calibration announcement frame may indicate silent versus loud information therein, as well as requires-silence and does-not-require-silence information therein.
Moreover, a given wireless communication device may employ one or more local decision criteria to determine whether or not a calibration operation of a given type should be performed therefore. As also described elsewhere herein, any of a variety of different local parameters and/or considerations (e.g., environmental conditions, processing history and/or behavior [such as on the transmit power control loop], built-in radio diagnostic functionality, elapsed time since the prior calibration operation, any other metrics, etc.) may be used to determine whether or not a calibration operation should be performed. Moreover, with respect to a given calibration operation to be performed, additional consideration may be made as to whether or not that calibration operation is a requires-silence calibration operation or a does-not-require-silence calibration operation. When a given wireless communication device receives a calibration announcement frame, it can use any of such various local parameters and/or considerations in determining whether or not to perform a calibration operation. There may be certain situations in which a calibration operation is not performed by a wireless communication device receiving a calibration announcement frame, even though it would be permissible to do so (e.g., based on the calibration announcement frame and/or one or more local decision criteria). In certain situations, while certain decision-making may not trigger the performance of a calibration operation, it may nonetheless be advantageous to perform such a calibration operation during an opportunity provided so that a subsequent calibration operation will not be needed until a later time (e.g., Such as in accordance with providing for less overall calibration operation frequency across various wireless dictation devices within the wireless communication system).
Referring to method 1200 of
The method 1200 continues by transmitting the calibration announcement frame from one wireless communication device to one or more other wireless communication devices, as shown in a block 1220.
The method 1200 then operates by performing the calibration operation, as shown in a block 1230. In certain embodiments, the operations of the block 1230 operate in accordance with one or more of the other wireless communication devices also performing a respective calibration operation, as shown in a block 1230a. That is to say, the operations of the block 1230a may be viewed as corresponding to that of a group calibration event.
In certain other embodiments, the operations of the block 1230 operate in accordance with one or more of the other wireless communication devices entering into a relatively more robust operational state, as shown in a block 1230b. By entering into such a relatively more robust an operational state from a relatively less robust operational state, the one or more of the other wireless communication devices will hopefully be less susceptible to interference that may be generated by the calibration operation of a given one of the wireless communication devices.
Referring to method 1201 of
The method 1201 then operates by selectively performing a respective calibration operation based on the calibration announcement frame and/or at least one local consideration, as shown in a block 1221. For example, in some embodiments, the selective performing of a respective calibration operation is based not only on the receiving of a calibration announcement frame, but also based upon one or more local considerations. For example, if a calibration operation has been performed relatively recently, then even though a calibration announcement frame may have been received, a given wireless communication device may not necessarily performed such a calibration a synchronization operation. Any of a number of other considerations as described herein may also be employed, in conjunction, to govern the consideration of whether or not to perform such calibration operation upon the receipt of a calibration announcement frame (e.g., processing history, temperature, etc.).
Referring to method 1202 of
The method 1202 then operates by selectively entering a relatively more robust operational state based on the calibration announcement frame and/or at least one local consideration, as shown in a block 1222. As may be understood with respect other embodiments described herein, in certain embodiments, the selective entering into a relatively more robust operational state from a relatively less robust operational state may be based upon not only the receiving of a calibration announcement frame, but also based upon one or more local considerations.
In certain embodiments, the operations of the block 1222 operate in accordance with entering into a cool down operational mode, as shown in a block 1222a. For example, such a cool down operational mode may specifically be tailored to reduce or cease operation of one or more components within a given device that generate a significant amount of heat. In certain other embodiments, the operations of the block 1222 operate in accordance with entering into a power down operational mode, as shown in a block 1222b. Certain embodiments will selectively power down only one or more components, while other embodiments will power down the entire device for a period of time.
In even other embodiments, the operations of the block 1222 operate in accordance with a power savings/low-power operational mode, as shown in a block 1222c. Generally speaking, the operations of the block 1222 operate in accordance with any desired modification of operation that assists, at least in part, in the selective entering into a relatively more robust operational state from a relatively less robust operational state, as shown in a block 1222b.
Referring to method 1300 of
The method 1300 continues by transmitting the calibration announcement frame from the wireless communication device to one or more other wireless communication devices indicating a maintenance window, as shown in a block 1320. Such a maintenance window may include respective time intervals corresponding to one or more wireless communication devices.
In certain embodiments, the operations of the block 1320 operate in accordance with a first wireless communication device operating during a first at least one interval, as shown in a block 1320a. In certain other embodiments, the operations of the block 1320 operate in accordance with a second wireless communication device operating during a second at least one interval, as shown in a block 1320b.
Referring to method 1301 of
The method 1301 then operates by performing a first of a plurality of calibration operations at a first respective time indicated within or based upon the calibration announcement frame and/or at least one local consideration, as shown in a block 1321.
As may be understood with respect other embodiments described herein, in certain embodiments, the performing of the first of the plurality of calibration operations may be based upon not only the receiving of a calibration announcement frame, but also based upon one or more local considerations.
The method 1301 continues by performing a second of the plurality of calibration operations at a second respective time indicated within or based upon the calibration announcement frame, the at least one local consideration, and/or at least one additional local consideration, as shown in a block 1331.
Referring to method 1400 of
The method 1400 continues by transmitting the calibration announcement frame from the first wireless communication device to one or more other wireless communication devices, as shown in a block 1420.
The method 1400 then continues by operating the first wireless communication device for performing a first respective calibration operation, as shown in a block 1430. The method 1400 then operates by operating a second wireless communication device for performing a second respective calibration operation, as shown in a block 1430. The method 1400 then continues by operating an n-th wireless communication device for performing an n-th respective calibration operation, as shown in a block 1430.
The method 1400 then operates by such that the operations of the blocks 1430, 1440, and so on up to 1450 may be performed simultaneously, in parallel, at the same time as one another. Generally speaking, any of a number of wireless communication devices may perform respective calibration operations. When two or more such wireless communication devices performed respective calibration operations simultaneously or in parallel with respect to each other, such operations may be viewed as a group calibration event.
Referring to method 1500 of
The method 1500 continues by adaptively determining whether to perform a calibration operation during at least a portion of the upcoming calibration interval, based on the calibration announcement frame, as shown in a block 1520. There may be some instances in which the first wireless communication device will be performing a respective calibration operation during the upcoming calibration interval. However, in other instances, the first wireless communication device will not be performing any calibration operation during the upcoming calibration interval.
Then, upon determination to perform the calibration operation, the method 1500 then operates by performing the calibration operation, as shown in a block 1530.
As described elsewhere. With respect other diagrams and/or embodiments, any of a variety of considerations may be made in accordance with the adaptive determination of whether to perform a calibration operation during the at least a portion of the upcoming calibration interval. For example, one or more indicia within the calibration announcement frame, one or more local criteria, etc. and/or any combination thereof may be considered in accordance with the adaptive determination of whether the first wireless communication device is to perform a calibration operation.
Referring to method 1501 of
The method 1501 then operates by analyzing the calibration announcement frame to identify a calibration operation indicated therein, as shown in a block 1521. For example, one or more indicia may be included within the calibration announcement frame corresponding to the type of calibration operation indicated therein. Such calibration operation indicated therein may correspond to that which will be performed by the second wireless communication device. As described elsewhere herein with respect to other diagrams and/or embodiments, such indicia may be included within the calibration announcement frame may indicate that the calibration operation indicated therein corresponds to a silent calibration operation or a loud calibration operation. Furthermore, such indicia may indicate that the calibration operation indicated within the calibration announcement frame corresponds to a requires-silence calibration operation or a does-not-require-silence calibration operation.
Based on the identified calibration operation (e.g., identified based upon the analysis of the calibration announcement frame) and at least one local decision criterion, the method 1501 continues by adaptively determining whether to perform at least one additional calibration operation during at least a portion of the upcoming calibration interval, as shown in a block 1531. For example, this at least one additional cooperation operation may be viewed as that which is performed by the first wireless communication device. As can be seen, at least two different levels of decision-making may be made in accordance with adaptively determining whether to perform at least one additional calibration operation during at least a portion of the upcoming calibration interval (e.g., Being specific and particular to the second wireless communication device). At least one level of decision-making may correspond to information that is identified based upon the analysis of the calibration announcement frame. At least one additional level of decision-making may correspond to one or more local decision criteria specific and particular to the first wireless communication device. Of course, any combination of this multi-level decision-making may be implemented within a given embodiment.
Then, upon determination to perform the calibration operation, the method 1501 then operates by performing the calibration operation, as shown in a block 1541.
It is also noted that the various operations and functions as described with respect to various methods herein may be performed within a wireless communication device, such as using a baseband processing module implemented therein (e.g., such as in accordance with the baseband processing module as described with reference to
It is noted that the various modules and/or circuitries (baseband processing modules and/or circuitries, encoding modules and/or circuitries, decoding modules and/or circuitries, etc., etc.) described herein may be a single processing device or a plurality of processing devices. Such a processing device may be a microprocessor, micro-controller, digital signal processor, microcomputer, central processing unit, field programmable gate array, programmable logic device, state machine, logic circuitry, analog circuitry, digital circuitry, and/or any device that manipulates signals (analog and/or digital) based on operational instructions. The operational instructions may be stored in a memory. The memory may be a single memory device or a plurality of memory devices. Such a memory device may be a read-only memory (ROM), random access memory (RAM), volatile memory, non-volatile memory, static memory, dynamic memory, flash memory, and/or any device that stores digital information. It is also noted that when the processing module implements one or more of its functions via a state machine, analog circuitry, digital circuitry, and/or logic circuitry, the memory storing the corresponding operational instructions is embedded with the circuitry comprising the state machine, analog circuitry, digital circuitry, and/or logic circuitry. In such an embodiment, a memory stores, and a processing module coupled thereto executes, operational instructions corresponding to at least some of the steps and/or functions illustrated and/or described herein.
It is also noted that any of the connections or couplings between the various modules, circuits, functional blocks, components, devices, etc. within any of the various diagrams or as described herein may be differently implemented in different embodiments. For example, in one embodiment, such connections or couplings may be direct connections or direct couplings there between. In another embodiment, such connections or couplings may be indirect connections or indirect couplings there between (e.g., with one or more intervening components there between). Of course, certain other embodiments may have some combinations of such connections or couplings therein such that some of the connections or couplings are direct, while others are indirect. Different implementations may be employed for effectuating communicative coupling between modules, circuits, functional blocks, components, devices, etc. without departing from the scope and spirit of the invention.
Various aspects of the present invention have also been described above with the aid of method steps illustrating the performance of specified functions and relationships thereof. The boundaries and sequence of these functional building blocks and method steps have been arbitrarily defined herein for convenience of description. Alternate boundaries and sequences can be defined so long as the specified functions and relationships are appropriately performed. Any such alternate boundaries or sequences are thus within the scope and spirit of the claimed invention.
Various aspects of the present invention have been described above with the aid of functional building blocks illustrating the performance of certain significant functions. The boundaries of these functional building blocks have been arbitrarily defined for convenience of description. Alternate boundaries could be defined as long as the certain significant functions are appropriately performed. Similarly, flow diagram blocks may also have been arbitrarily defined herein to illustrate certain significant functionality. To the extent used, the flow diagram block boundaries and sequence could have been defined otherwise and still perform the certain significant functionality. Such alternate definitions of both functional building blocks and flow diagram blocks and sequences are thus within the scope and spirit of the claimed invention.
One of average skill in the art will also recognize that the functional building blocks, and other illustrative blocks, modules and components herein, can be implemented as illustrated or by discrete components, application specific integrated circuits, processors executing appropriate software and the like or any combination thereof.
Moreover, although described in detail for purposes of clarity and understanding by way of the aforementioned embodiments, various aspects of the present invention are not limited to such embodiments. It will be obvious to one of average skill in the art that various changes and modifications may be practiced within the spirit and scope of the invention, as limited only by the scope of the appended claims.
Mode Selection Tables:
Claims
1. An apparatus, comprising:
- a radio for receiving a calibration announcement frame from a wireless communication device indicating an upcoming calibration interval; and
- a processing module for: analyzing the calibration announcement frame to identify a first calibration operation to be performed by the wireless communication device; based on the first calibration operation and at least one local decision criterion corresponding to the apparatus, adaptively determining whether to perform a second calibration operation during at least a portion of the upcoming calibration interval; and upon determination to perform the second calibration operation, directing the apparatus to perform the calibration operation.
2. The apparatus of claim 1, wherein:
- the first calibration operation corresponding to:
- a loud and requires-silence calibration operation;
- a loud and does-not-require-silence calibration operation;
- a silent and requires-silence calibration operation; or
- a silent and does-not-require-silence calibration operation.
3. The apparatus of claim 1, wherein:
- the at least one local decision criterion corresponding to at least one of a processing history, a temperature, a temperature change, a humidity level, a humidity level change, a period of time from a previous calibration operation, and whether the calibration operation being a loud and requires-silence calibration operation, a loud and does-not-require-silence calibration operation, a silent and requires-silence calibration operation, or a silent and does-not-require-silence calibration operation.
4. The apparatus of claim 1, wherein:
- based on the calibration announcement frame, the processing module for directing the apparatus to perform at least one of: enter a relatively more robust operational state from a relatively less robust operational state; make no communication during the upcoming calibration interval.
5. The apparatus of claim 1, wherein:
- based on the calibration announcement frame, the processing module for informing an application layer of the apparatus, relatively higher than a physical (PHY) layer of the apparatus, of the upcoming calibration interval; and
- the application layer for adaptively determining whether to perform at least one operation during the at least a portion of the upcoming calibration interval and performing the at least one operation upon determination thereof.
6. The apparatus of claim 1, wherein:
- the calibration announcement frame indicating a maintenance window including a plurality of time intervals such that at least one of the plurality of time intervals corresponding to the apparatus during which the apparatus permitted to perform the calibration operation or at least one additional operation.
7. The apparatus of claim 1, wherein:
- the calibration announcement frame being a clear to send (CTS2SELF) communication frame, a beacon, or a broadcast packet.
8. The apparatus of claim 1, wherein:
- the apparatus being a wireless station (STA);
- the wireless communication device being an access point (AP) or at least one additional STA.
9. An apparatus, comprising:
- a radio for receiving a calibration announcement frame from a wireless communication device indicating an upcoming calibration interval; and
- a processing module for: based on the calibration announcement frame, adaptively determining whether to perform a calibration operation during at least a portion of the upcoming calibration interval; and upon determination to perform the calibration operation, directing the apparatus to perform the calibration operation.
10. The apparatus of claim 9, wherein:
- the processing module for: analyzing the calibration announcement frame to identify at least one additional calibration operation to be performed by the wireless communication device; based on the at least one additional calibration operation, adaptively determining whether to perform the calibration operation during the at least a portion of the upcoming calibration interval; and upon determination to perform the calibration operation, directing the apparatus to perform the calibration operation.
11. The apparatus of claim 10, wherein:
- the at least one additional calibration operation corresponding to:
- a loud and requires-silence calibration operation;
- a loud and does-not-require-silence calibration operation;
- a silent and requires-silence calibration operation; or
- a silent and does-not-require-silence calibration operation.
12. The apparatus of claim 9, wherein:
- the processing module for considering at least one local decision criterion corresponding to the apparatus in accordance with adaptively determining whether to perform the calibration operation during the at least a portion of the upcoming calibration interval.
13. The apparatus of claim 12, wherein:
- the at least one local decision criterion corresponding to at least one of a processing history, a temperature, a temperature change, a humidity level, a humidity level change, a period of time from a previous calibration operation, and whether the calibration operation being a loud and requires-silence calibration operation, a loud and does-not-require-silence calibration operation, a silent and requires-silence calibration operation, or a silent and does-not-require-silence calibration operation.
14. The apparatus of claim 9, wherein:
- based on the calibration announcement frame, the processing module for directing the apparatus to perform at least one of: enter a relatively more robust operational state from a relatively less robust operational state; make no communication during the upcoming calibration interval.
15. The apparatus of claim 9, wherein:
- based on the calibration announcement frame, the processing module for informing an application layer of the apparatus, relatively higher than a physical (PHY) layer of the apparatus, of the upcoming calibration interval; and
- the application layer for adaptively determining whether to perform at least one operation during the at least a portion of the upcoming calibration interval and performing the at least one operation upon determination thereof.
16. The apparatus of claim 9, wherein:
- the calibration announcement frame indicating a maintenance window including a plurality of time intervals such that at least one of the plurality of time intervals corresponding to the apparatus during which the apparatus permitted to perform the calibration operation or at least one additional operation.
17. The apparatus of claim 9, wherein:
- the calibration announcement frame being a clear to send (CTS2SELF) communication frame, a beacon, or a broadcast packet.
18. The apparatus of claim 9, wherein:
- the apparatus being a wireless station (STA);
- the wireless communication device being an access point (AP) or at least one additional STA.
19. A method for operating a first wireless communication device, the method comprising:
- via a wireless communication channel, receiving a calibration announcement frame from a second wireless communication device indicating an upcoming calibration interval;
- based on the calibration announcement frame, adaptively determining whether to perform a calibration operation during at least a portion of the upcoming calibration interval; and
- upon determination to perform the calibration operation, performing the calibration operation.
20. The method of claim 19, further comprising:
- analyzing the calibration announcement frame to identify at least one additional calibration operation to be performed by the wireless communication device;
- based on the at least one additional calibration operation, adaptively determining whether to perform the calibration operation during the at least a portion of the upcoming calibration interval; and
- upon determination to perform the calibration operation, performing the calibration operation.
21. The method of claim 20, wherein:
- the at least one additional calibration operation corresponding to:
- a loud and requires-silence calibration operation;
- a loud and does-not-require-silence calibration operation;
- a silent and requires-silence calibration operation; or
- a silent and does-not-require-silence calibration operation.
22. The method of claim 19, further comprising:
- considering at least one local decision criterion corresponding to the first wireless communication device in accordance with adaptively determining whether to perform the calibration operation during the at least a portion of the upcoming calibration interval.
23. The method of claim 22, wherein:
- the at least one local decision criterion corresponding to at least one of a processing history, a temperature, a temperature change, a humidity level, a humidity level change, a period of time from a previous calibration operation, and whether the calibration operation being a loud and requires-silence calibration operation, a loud and does-not-require-silence calibration operation, a silent and requires-silence calibration operation, or a silent and does-not-require-silence calibration operation.
24. The method of claim 19, further comprising:
- based on the calibration announcement frame, performing at least one of: entering a relatively more robust operational state from a relatively less robust operational state; making no communication during the upcoming calibration interval.
25. The method of claim 19, further comprising:
- based on the calibration announcement frame, informing an application layer of the first wireless communication device, relatively higher than a physical (PHY) layer of the first wireless communication device, of the upcoming calibration interval; and wherein:
- the application layer adaptively determining whether to perform at least one operation during the at least a portion of the upcoming calibration interval and performing the at least one operation upon determination thereof.
26. The method of claim 19, wherein:
- the calibration announcement frame indicating a maintenance window including a plurality of time intervals such that at least one of the plurality of time intervals corresponding to the apparatus during which the apparatus permitted to perform the calibration operation or at least one additional operation.
27. The method of claim 19, wherein:
- the calibration announcement frame being a clear to send (CTS2SELF) communication frame, a beacon, or a broadcast packet.
28. The method of claim 19, wherein:
- the first wireless communication device being a wireless station (STA);
- the second wireless communication device being an access point (AP) or at least one additional STA.
Type: Application
Filed: Jul 12, 2011
Publication Date: Dec 6, 2012
Applicant: BROADCOM CORPORATION (IRVINE, CA)
Inventors: Peyush Agarwal (Milpitas, CA), Joachim S. Hammerschmidt (Mountain View, CA), Yasantha N. Rajakarunanayake (San Ramon, CA)
Application Number: 13/180,843
International Classification: H04B 17/00 (20060101);
