Non-Beacon Network Communications Using Frequency Subbands
Systems and methods for designing, using, and/or implementing non-beacon network communications using frequency subbands are described. In various implementations, these systems and methods may be applicable to Power Line Communications (PLC). For example, a method may include transmitting a beacon request message over a given one of a plurality of frequency subbands, receiving a plurality of beacons in response to having transmitted the beacon request message, each of the plurality of beacons received over a respective one of the plurality of frequency subbands, and calculating a downlink quality report based, at least in part, upon the received beacons. The method may also include transmitting the downlink quality report over each of the plurality of frequency subbands and receiving a subband allocation command in response to having transmitted the downlink quality report, the subband allocation command indicating a downlink subband assignment and an uplink subband assignment.
This application is a continuation of U.S. Nonprovisional patent application Ser. No. 13/457,590, filed Apr. 27, 2012 (now U.S. Pat. No. 8,885,505), which claims the benefit of the filing date of U.S. Provisional Patent Application No. 61/480,028 titled “Non Beacon Mode Multi Tone Mask MAC Protocol for MV-LV PLC Networks” and filed Apr. 28, 2011, the disclosure of which is hereby incorporated by reference herein in its entirety.
TECHNICAL FIELDThis specification is directed, in general, to network communications, and, more specifically, to systems and methods for designing, using, and/or implementing non-beacon network communications using frequency subbands.
BACKGROUNDThere are several different types of network communications available today. For example, power line communications (PLC) include systems for communicating data over the same medium (i.e., a wire or conductor) that is also used to transmit electric power to residences, buildings, and other premises. Once deployed, PLC systems may enable a wide array of applications, including, for example, automatic meter reading and load control (i.e., utility-type applications), automotive uses (e.g., charging electric cars), home automation (e.g., controlling appliances, lights, etc.), and/or computer networking (e.g., Internet access), to name only a few.
For each different type of communications network, different standardizing efforts are commonly undertaken throughout the world. For instance, in the case of PLC communications may be implemented differently depending upon local regulations, characteristics of local power grids, etc. Examples of competing PLC standards include the IEEE 1901, HomePlug AV, and ITU-T G.hn (e.g., G.9960 and G.9961) specifications. Another PLC standardization effort includes, for example, the Powerline-Related Intelligent Metering Evolution (PRIME) standard designed for OFDM-based (Orthogonal Frequency-Division Multiplexing) communications.
SUMMARYSystems and methods for designing, using, and/or implementing non-beacon network communications using frequency subbands are described. In an illustrative, non-limiting embodiment, a method may include transmitting a beacon request message over a given one of a plurality of frequency subbands, receiving a plurality of beacons in response to having transmitted the beacon request message, each of the plurality of beacons received over a respective one of the plurality of frequency subbands, and calculating a downlink quality report based, at least in part, upon the received beacons. The method may also include transmitting the downlink quality report over each of the plurality of frequency subbands and receiving a subband allocation command in response to having transmitted the downlink quality report, the subband allocation command indicating a downlink subband assignment and an uplink subband assignment.
In some implementations, the beacon request message may indicate a sequence of frequency subbands over which the plurality of beacons is transmitted by other devices that are already a part of the network (e.g., including a data concentrator or the like) and/or a sequence of frequency subbands over which the downlink quality report is transmitted. The downlink quality report may include a downlink channel quality indicator for each of the plurality of subbands (which may be usable by other devices to estimate an uplink quality in each of the plurality of subbands) and/or it may indicate a downlink subband chosen by the communication device among the plurality of plurality of subbands.
Moreover, receiving the subband allocation command may include receiving the allocation command over the chosen downlink subband. For example, the subband allocation command may identify uplink subbands chosen by other devices. Additionally or alternatively, allocated downlink subband assignment may identify an assigned downlink subband that is the same or different than the chosen downlink subband. The method may also include communicating with a PLC device using the downlink subband assignment and the uplink subband assignment.
In another illustrative, non-limiting embodiment, a method may include transmitting, to a PLC data concentrator, a beacon request message over a given one of a plurality of frequency subbands and receive a plurality of beacons from the PLC data concentrator in response to having transmitted the beacon request message, each of the plurality of beacons received over a respective one of the plurality of frequency subbands. The method may also include calculating a downlink quality report based, at least in part, upon the received beacons, and transmitting an uplink scan initiation request to the PLC data concentrator over the given one of the plurality of frequency subbands, the uplink scan initiation request indicating a chosen one of the plurality of frequency subbands.
In some implementations, the method may include receiving an uplink scan initiation command from the PLC data concentrator in response to the uplink scan initiation request over the chosen one of the plurality of frequency subbands, the uplink scan initiation request indicating a downlink subband assignment to be used in subsequent communications. The method may also include transmitting the downlink quality report to the PLC data concentrator over each of the plurality of frequency subbands in response to the uplink scan initiation command. The method may further include receiving a subband allocation command from the PLC data concentrator in response to having transmitted the downlink quality report, the subband allocation command received over the downlink subband assignment, the subband allocation command indicating an uplink subband assignment to be used in subsequent communications.
Additionally or alternatively, in response to not receiving an uplink scan initiation command from the PLC data concentrator, the method may include transmitting another beacon request message to the PLC data concentrator over each of the plurality of subbands, the PLC data concentrator configured to select an uplink subband based, at least in part, upon the other beacon requests.
In yet another illustrative, non-limiting embodiment, a method may include receiving, from a PLC device, a beacon request message over a given one of a plurality of frequency subbands, transmitting a plurality of beacons to the PLC device, each of the plurality of beacons transmitted over a respective one of the plurality of frequency subbands, and receiving a downlink quality report from the PLC device over each of the plurality of frequency subbands. The method may also include transmitting a subband allocation command to the PLC device, the subband allocation command indicating an uplink subband assignment to be used in subsequent communications with the PLC device.
In some implementations, prior to having received the downlink quality report, the method may include receiving an uplink scan initiation request from the PLC device over the given one of the plurality of frequency subbands, the uplink scan initiation request indicating a chosen one of the plurality of frequency subbands suitable for subsequent downlink communications. The method may also include transmitting an uplink scan initiation command to the PLC device in response to the uplink scan initiation request over the chosen one of the plurality of frequency subbands, the uplink scan initiation request indicating a downlink subband assignment to be used in subsequent communications.
In some embodiments, one or more communication devices or computer systems may perform one or more of the techniques described herein. In other embodiments, a tangible computer-readable or electronic storage medium may have program instructions stored thereon that, upon execution by one or more communication devices or computer systems, cause the one or more communication devices or computer systems to execute one or more operations disclosed herein. In yet other embodiments, a communication system (e.g., a device or modem) may include at least one processor and a memory coupled to the at least one processor. Examples of a processor include, but are not limited to, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a system-on-chip (SoC) circuit, a field-programmable gate array (FPGA), a microprocessor, or a microcontroller. The memory may be configured to store program instructions executable by the at least one processor to cause the system to execute one or more operations disclosed herein.
Having thus described the invention(s) in general terms, reference will now be made to the accompanying drawings, wherein:
The invention(s) now will be described more fully hereinafter with reference to the accompanying drawings. The invention(s) may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention(s) to a person of ordinary skill in the art. A person of ordinary skill in the art may be able to use the various embodiments of the invention(s).
In various embodiments, the systems and methods described herein may be used to design and/or non-beacon network communications using frequency subbands. Generally speaking, these systems and methods may be applicable to a wide variety of communication environments, including, but not limited to, those involving wireless communications (e.g., cellular, Wi-Fi, WiMax, etc.), wired communications (e.g., Ethernet, etc.), power line communications (PLC), or the like. For ease of explanation, several examples discussed below are described specifically in the context of PLC. As a person of ordinary skill in the art will recognize in light of this disclosure, however, certain techniques and principles disclosed herein may also be applicable to other communication environments.
Turning now to
The power line topology illustrated in
An illustrative method for transmitting data over power lines may use, for example, a carrier signal having a frequency different from that of the power signal. The carrier signal may be modulated by the data, for example, using an orthogonal frequency division multiplexing (OFDM) scheme or the like.
PLC modems or gateways 112a-n at residences 102a-n use the MV/LV power grid to carry data signals to and from PLC data concentrator 114 without requiring additional wiring. Concentrator 114 may be coupled to either MV line 103 or LV line 105. Modems or gateways 112a-n may support applications such as high-speed broadband Internet links, narrowband control applications, low bandwidth data collection applications, or the like. In a home environment, for example, modems or gateways 112a-n may further enable home and building automation in heat and air conditioning, lighting, and security. Also, PLC modems or gateways 112a-n may enable AC or DC charging of electric vehicles and other appliances. An example of an AC or DC charger is illustrated as PLC device 113. Outside the premises, power line communication networks may provide street lighting control and remote power meter data collection.
One or more data concentrators 114 may be coupled to control center 130 (e.g., a utility company) via network 120. Network 120 may include, for example, an IP-based network, the Internet, a cellular network, a WiFi network, a WiMax network, or the like. As such, control center 130 may be configured to collect power consumption and other types of relevant information from gateway(s) 112 and/or device(s) 113 through concentrator(s) 114. Additionally or alternatively, control center 130 may be configured to implement smart grid policies and other regulatory or commercial rules by communicating such rules to each gateway(s) 112 and/or device(s) 113 through concentrator(s) 114.
In some embodiments, each concentrator 114 may be seen as a base node for a PLC domain, each such domain comprising downstream PLC devices that communicate with control center 130 through a respective concentrator 114. For example, in
Still referring to
PLC engine 202 may be configured to transmit and/or receive PLC signals over wires 108a and/or 108b via AC interface 201 using a particular channel or frequency band. In some embodiments, PLC engine 202 may be configured to transmit OFDM signals, although other types of modulation schemes may be used. As such, PLC engine 202 may include or otherwise be configured to communicate with metrology or monitoring circuits (not shown) that are in turn configured to measure power consumption characteristics of certain devices or appliances via wires 108, 108a, and/or 108b. PLC engine 202 may receive such power consumption information, encode it as one or more PLC signals, and transmit it over wires 108, 108a, and/or 108b to higher-level PLC devices (e.g., PLC gateways 112n, data concentrators 114, etc.) for further processing. Conversely, PLC engine 202 may receive instructions and/or other information from such higher-level PLC devices encoded in PLC signals, for example, to allow PLC engine 202 to select a particular frequency band in which to operate.
In various embodiments, PLC device 113 may be implemented at least in part as an integrated circuit.
Peripherals 304 may include any desired circuitry, depending on the type of PLC device or system. For example, in some embodiments, peripherals 304 may implement, at least in part, at least a portion of a PLC modem (e.g., portions of AC interface 210 shown in
In various implementations, PLC device or modem 113 may include transmitter and/or receiver circuits configured to connect to power lines 103, 105, and/or 108.
Turning to
Within network 700, communications may be achieved between or among devices using one or more different frequency subbands (also referred to as “tone masks” or “channels”) in the downlink and uplink directions. Generally speaking, the term “downlink” refers to a communication in a direction that is received by a given device, and the term “uplink” refers to a communication in a direction that is transmitted by that same device. In the case of MV-LV communications, however, the term “downlink” refers to links or communications taking place from an MV device to an LV device, and the term “uplink” refers to links or communications taking place from an LV device to an MV device.
In a typical case, the frequency subband over which an MV device can communicate with an LV device (downlink) may be different from the subband that the LV device may used to communicate with an MV device (uplink). Also, the uplink and downlink subbands may be different between different LV devices communicating with the same MV device. As such, each PLC device involved in a communication may select (or allow another device to select) good or best communication channels or subbands, for example, based upon a determination of channel conditions (e.g., signal-to-noise ratio (SNR) measurements, congestion indicators, etc.) or the like.
In various embodiments, the PLC devices described above (and/or the computer system shown in
For example, in some implementations, communications between MV1 and MV2 may be performed using poll-based data transfer with carrier sense multiple access (CSMA) or other carrier access (CA) technique. Communications between MV1 and MV3 may be performed using beacon mode CSMA/CA during an allocated time. Communications between MV devices and first-level LV devices may be performed using poll-based Contention Free Period(s) (CFP) over a given frequency subband. Communications between first- and second-level LV devices may be performed using wideband CSMA/CA operations blocked out for periods of time for subband operation, and communications between lower-level LV devices may be performed using wideband CSMA/CA operational at all times. These and other operations are discussed below.
MV Operation
Accordingly, an MV device may tune its receiver to different subbands over a period of time, as shown in
In some implementations, the MV device's switching among frequency subbands (e.g., 805a-805b-805a- . . . -805n), as well as their durations, may be random. Additionally or alternatively, it may follow a selected pattern or sequence of frequency subbands and/or durations. In some cases, the MV device may be capable of tuning its receiver to two or more distinct frequency subbands at the same time (e.g., subbands 805a and 805b), in addition or as an alternative to being able to operate in wideband (i.e., subbands 805a through 805n).
LV-MV Scanning
With respect to LV-MV scanning or discovery, an LV node (e.g., LV11 shown in
At block 925, the LV device may calculate a downlink quality report based, at least in part, upon the received beacons. For example, such a report may include a measured or estimated channel or link quality metric (e.g., signal-to-noise ratio or SNR, etc.) for each frequency subband. Still at block 925, the LV device may select one of the frequency subbands suitable for subsequent downlink communications—e.g., it may select the subband with highest SNR or the like, according to the report. In this example, assume that the selected downlink subband is subband 2. Then, at block 930, the LV device may transmit the downlink quality report and/or the selected downlink subband as messages, packets, or frames 1015 over each of the frequency subbands in the same order as the LV tone mask sequence. Alternatively, the LV device may transmit beacon requests over each of the plurality of subbands.
At block 935, the MV device may receive the downlink quality reports 1015 (or beacon requests), and may create an uplink quality report based on those signals. The MV device may also select or assign a downlink subband (based on the downlink quality report or beacon requests), as well as an uplink subband (based on the uplink quality report) to the LV device. As such, at block 940, the MV device may transmit subband allocation command 1020 indicating those assignments to the LV device over the downlink frequency subband chosen by the LV device. At block 945, the LV device may tune its receiver to the chosen subband and it may receive subband allocation command 1020. The LV device may then conduct subsequent communications with the MV device using the assigned downlink and uplink frequency subbands.
In some cases, the MV device may assign a downlink frequency subband to the LV device that is different from the subband chosen by the LV device at block 925. For example, the chosen downlink subband may be subband 2 (over which the mask allocation command is received), but the assigned subband may be subband 1 or 3. Generally speaking, the LV device may select what it perceives to be a good or best downlink subband based on the measured or estimated channel quality metrics. However, the MV device may take other criteria into account such as, for example, the level of congestion in the downlink direction (i.e., whether or how many other devices are already using that subband, etc.), when assigning a downlink subband for future communications. In other words, although the downlink subband assigned by the MV device may be “sub-optimal” from the perspective of the LV device in terms of channel or link quality, it may nonetheless result in better overall network performance.
Typically, when employing the techniques shown in
Specifically,
In contrast with the techniques illustrated in
At block 1145, the LV device may receive uplink scan initiate command 1220 and it may transmit the downlink quality report as messages, packets, or frames 1225 over each of the frequency subbands in the same order as the LV tone mask sequence at block 1150. (Similarly as above, the LV device may transmit beacon requests instead of downlink quality reports over each of subband.) At block 1155, the MV device may receive the downlink quality reports 1225 (or beacon requests), and may create an uplink quality report based on those signals. The MV device may also select or assign an uplink subband (based on the uplink quality report) to the LV device. As such, at block 1160, the MV device may transmit subband allocation command 1230 indicating the uplink subband assignment to the LV device over the downlink frequency subband previously assigned via uplink scan initiation command 1220 (in some cases, subband allocation command 1230 may include both the uplink and the downlink assignments). At block 1165, the LV device may tune its receiver to the assigned the downlink frequency subband and it may receive subband allocation command 1230. The LV device may then conduct subsequent communications with the MV device using the assigned downlink and uplink frequency subbands.
Again, compared with the methods described in
LV-LV and MV-MV Scanning
In various embodiments, LV-LV scanning (e.g., between two LV devices of the same or different levels) may be performed on wideband (i.e., using all available frequency subbands). A new LV node may send a beacon request on wideband (e.g., periodically) using CSMA/CA or the like. An LV switch node or coordinator (e.g., a first-level LV device) may then respond to beacon request with beacon so long as the LV switch node or coordinator is listening on wideband (in some implementations, first-level devices only), no collision occurred on the beacon request frame, and there is no frame error due to noise in the channel.
The MV-MV scanning procedure may be similar to LV-LV scanning procedure. Specifically, a new MV node may send a beacon request on wideband periodically. An MV coordinator may then respond to beacon requests if: the MV coordinator is listening on wideband, no collision occurred on the beacon request frame, and no frame error due to noise in the channel. In some implementations, MV-MV scanning may always take place over wideband.
Data Transfers (Steady State)
After tone mask selection, a first-level LV device (e.g., LV11) may listen on its assigned downlink tone mask for poll and/or downlink data, as well as wideband for uplink data from lower-level nodes (e.g., LV22). For example, LV11 may use poll-based CFP for uplink data transmissions. An MV device may send a poll command using LV11's assigned downlink tone mask and, it may switch to LV11's assigned uplink tone mask for any potential reception (e.g., after starting a timer). Prior to responding to the MV device's poll requests, LV11 may transmit a clear-to-send-to-self (“CTS-2-Self”) frame in order to block lower-level devices from transmitting on wideband for the duration of LV11's uplink transmission. Moreover, LV11 may respond to the poll request with uplink data on the assigned uplink tone mask. If LV11 does not have uplink data to transmit, the MV device may time out, and then it may poll other LV devices.
In some implementations, the MV device may transmit data to LV11 over the assigned downlink tone mask. For example, the MV node may transmit a poll with a time indication for downlink data transmission, so that LV11 may forward this information in a CTS-2-Self frame to block lower-level LV nodes from transmitting on wideband. Also, because LV11 is listening on the assigned downlink tone mask by default, it may be able to receive the downlink data following the MV's poll. For uplink acknowledgement (“ACK”) transmissions, LV may switch to its assigned uplink tone mask after a downlink data reception to transmit the ACK. Conversely, for downlink ACK transmissions, the MV device may switch to LV11's assigned downlink tone mask after an uplink data reception. ACK packets may be transmitted immediately or as block ACK, which may be negotiated during connection setup. In some embodiments, LV11 may also listen on wideband for any uplink transmissions from lower-level LV devices. If a lower-level LV device transmits while there are no poll-CFP packets, its receiver may be tuned to the wideband.
MV-MV communications may take place similarly as described above. Specifically, MV-MV communication may occur on wideband when there is no polling for MV-LV11 communication. It may also employ CSMA/CA—based communication on wideband when first-level LV nodes communicate with lower-level LV nodes. Furthermore, the MV coordinator may prevent unnecessary transmissions on wideband when polling for first-level LV nodes by transmitting CTS-2-Self frames for the desired duration (e.g., when operating on a tone-mask). LV-LV communications may also be similar. First-level LV nodes may prevent any unnecessary transmissions on wideband when communicating with MV node by transmitting CTS-2-Self frames for the desired duration (when operating on a tone-mask). At all other times and at third-level and below, communications may employ CSMA/CA-based communication on wideband.
As previously noted, in certain embodiments, systems and methods for designing, using, and/or non-beacon network communications using frequency subbands may be executed, at least in part, by one or more communication devices and/or computer systems. One such computer system is illustrated in
As illustrated, system 1300 includes one or more processors 1310 coupled to a system memory 1320 via an input/output (I/O) interface 1330. Computer system 1300 further includes a network interface 1340 coupled to I/O interface 1330, and one or more input/output devices 1325, such as cursor control device 1360, keyboard 1370, display(s) 1380, and/or mobile device 1390. In various embodiments, computer system 1300 may be a single-processor system including one processor 1310, or a multi-processor system including two or more processors 1310 (e.g., two, four, eight, or another suitable number). Processors 1310 may be any processor capable of executing program instructions. For example, in various embodiments, processors 1310 may be general-purpose or embedded processors implementing any of a variety of instruction set architectures (ISAs), such as the x86, POWERPC®, ARM®, SPARC®, or MIPS® ISAs, or any other suitable ISA. In multi-processor systems, each of processors 1310 may commonly, but not necessarily, implement the same ISA. Also, in some embodiments, at least one processor 1310 may be a graphics processing unit (GPU) or other dedicated graphics-rendering device.
System memory 1320 may be configured to store program instructions and/or data accessible by processor 1310. In various embodiments, system memory 1320 may be implemented using any suitable memory technology, such as static random access memory (SRAM), synchronous dynamic RAM (SDRAM), nonvolatile/Flash-type memory, or any other type of memory. As illustrated, program instructions and data implementing certain operations such as, for example, those described in the figures above, may be stored within system memory 1320 as program instructions 1325 and data storage 1335, respectively. In other embodiments, program instructions and/or data may be received, sent or stored upon different types of computer-accessible media or on similar media separate from system memory 1320 or computer system 1300. Generally speaking, a computer-accessible medium may include any tangible storage media or memory media such as magnetic or optical media—e.g., disk or CD/DVD-ROM coupled to computer system 1300 via I/O interface 1330. Program instructions and data stored on a tangible computer-accessible medium in non-transitory form may further be transmitted by transmission media or signals such as electrical, electromagnetic, or digital signals, which may be conveyed via a communication medium such as a network and/or a wireless link, such as may be implemented via network interface 1340.
In one embodiment, I/O interface 1330 may be configured to coordinate I/O traffic between processor 1310, system memory 1320, and any peripheral devices in the device, including network interface 1340 or other peripheral interfaces, such as input/output devices 1350. In some embodiments, I/O interface 1330 may perform any necessary protocol, timing or other data transformations to convert data signals from one component (e.g., system memory 1320) into a format suitable for use by another component (e.g., processor 1310). In some embodiments, I/O interface 1330 may include support for devices attached through various types of peripheral buses, such as a variant of the Peripheral Component Interconnect (PCI) bus standard or the Universal Serial Bus (USB) standard, for example. In some embodiments, the function of I/O interface 1330 may be split into two or more separate components, such as a north bridge and a south bridge, for example. In addition, in some embodiments some or all of the functionality of I/O interface 1330, such as an interface to system memory 1320, may be incorporated directly into processor 1310.
Network interface 1340 may be configured to allow data to be exchanged between computer system 1300 and other devices attached to a network, such as other computer systems, or between nodes of computer system 1300. In various embodiments, network interface 1340 may support communication via wired or wireless general data networks, such as any suitable type of Ethernet network, for example; via telecommunications/telephony networks such as analog voice networks or digital fiber communications networks; via storage area networks such as Fibre Channel SANs, or via any other suitable type of network and/or protocol.
Input/output devices 1350 may, in some embodiments, include one or more display terminals, keyboards, keypads, touchpads, scanning devices, voice or optical recognition devices, mobile devices, or any other devices suitable for entering or retrieving data by one or more computer system 1300. Multiple input/output devices 1350 may be present in computer system 1300 or may be distributed on various nodes of computer system 1300. In some embodiments, similar input/output devices may be separate from computer system 1300 and may interact with one or more nodes of computer system 1300 through a wired or wireless connection, such as over network interface 1340.
As shown in
A person of ordinary skill in the art will appreciate that computer system 1300 is merely illustrative and is not intended to limit the scope of the disclosure described herein. In particular, the computer system and devices may include any combination of hardware or software that can perform the indicated operations. In addition, the operations performed by the illustrated components may, in some embodiments, be performed by fewer components or distributed across additional components. Similarly, in other embodiments, the operations of some of the illustrated components may not be provided and/or other additional operations may be available. Accordingly, systems and methods described herein may be implemented or executed with other computer system configurations.
It will be understood that various operations discussed herein may be executed simultaneously and/or sequentially. It will be further understood that each operation may be performed in any order and may be performed once or repetitiously. In various embodiments, the operations discussed herein may represent sets of software routines, logic functions, and/or data structures that are configured to perform specified operations. Although certain operations may be shown as distinct logical blocks, in some embodiments at least some of these operations may be combined into fewer blocks. Conversely, any given one of the blocks shown herein may be implemented such that its operations may be divided among two or more logical blocks. Moreover, although shown with a particular configuration, in other embodiments these various modules may be rearranged in other suitable ways.
Many of the operations described herein may be implemented in hardware, software, and/or firmware, and/or any combination thereof. When implemented in software, code segments perform the necessary tasks or operations. The program or code segments may be stored in a processor-readable, computer-readable, or machine-readable medium. The processor-readable, computer-readable, or machine-readable medium may include any device or medium that can store or transfer information. Examples of such a processor-readable medium include an electronic circuit, a semiconductor memory device, a flash memory, a ROM, an erasable ROM (EROM), a floppy diskette, a compact disk, an optical disk, a hard disk, a fiber optic medium, etc. Software code segments may be stored in any volatile or non-volatile storage device, such as a hard drive, flash memory, solid state memory, optical disk, CD, DVD, computer program product, or other memory device, that provides tangible computer-readable or machine-readable storage for a processor or a middleware container service. In other embodiments, the memory may be a virtualization of several physical storage devices, wherein the physical storage devices are of the same or different kinds. The code segments may be downloaded or transferred from storage to a processor or container via an internal bus, another computer network, such as the Internet or an intranet, or via other wired or wireless networks.
Many modifications and other embodiments of the invention(s) will come to mind to one skilled in the art to which the invention(s) pertain having the benefit of the teachings presented in the foregoing descriptions, and the associated drawings. Therefore, it is to be understood that the invention(s) are not to be limited to the specific embodiments disclosed. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.
Claims
1-20. (canceled)
21. A method comprising:
- performing, using a communication device, transmitting a beacon request message over a given one of a plurality of frequency subbands; receiving a plurality of beacons in response to having transmitted the beacon request message, each of the plurality of beacons received over a respective one of the plurality of frequency subbands; calculating a downlink quality report based, at least in part, upon the received beacons; transmitting the downlink quality report over each of the plurality of frequency subbands; and receiving a subband allocation command in response to having transmitted the downlink quality report, the subband allocation command indicating a downlink subband assignment and an uplink subband assignment.
Type: Application
Filed: Nov 11, 2014
Publication Date: Mar 5, 2015
Inventors: Ramanuja Vedantham (Allen, TX), Kumaran Vijayasankar (Dallas, TX), Anand G. Dabak (Plano, TX), Badri N. Varadarajan (Mountain View, CA)
Application Number: 14/538,425
International Classification: H04W 72/04 (20060101); H04W 72/12 (20060101);