Abstract: A method for selecting antenna elements at a base station can include selecting multiple transmit antenna elements from several antenna elements according to a work mode of the base station. The work mode can be an open-loop or a closed-loop working mode. In open-loop mode the base station does not receive feedback information regarding channel quality from a mobile station. In closed-loop mode feedback information is received. For example, for control signaling, or when the speed of a mobile station is very high, the base station may determine that the working mode is open-loop. When the information being transmitted is data for a specific mobile station and the mobile station is moving at a speed under a threshold, the base station may select or determine the working mode to be the closed-loop working mode. Antenna elements are selected, for example, according to a spatial correlation appropriate to the work mode.

Abstract: A pre-distortion circuit that may introduce a pre-distortion signal in a communication channel by determining a harmonic signal of the signal to be output. One or more image correction signals of the signal to be output may be determined. The one or more image correction signals may be complex conjugate signal variations of the signal to be output. The harmonic signal, the one or more image correction signals and the signal to be output may be combined into a combined output signal. The combined output signal may be transmitted to a digital-to-analog converter. The predistortion circuit may be implemented in a FPGA, an ASIC, a digital-to-analog converter, and/or a separate IC package.

Abstract: Provided is a method of wireless communication which includes selecting a codebook from a plurality of codebooks in accordance with an antenna characteristic, and transmitting an indication of the selected codebook. Each of the plurality of codebooks is associated with one of a plurality of antenna characteristics. In some designs, channel state information is received from a user equipment. The channel state information may be used to determine downlink scheduling and/or precoding. In some designs, the channel state information may include feedback elements associated with different subband granularity. The feedback elements may also indicate a selection of a subset of precoder column vectors and/or a phase offset between two groups of transmit antennas.

Abstract: A mobile station device transmits a random access preamble, whose preamble ID is randomly selected by the mobile station device, to a base station device and performs uplink timing alignment based on the synchronization timing deviation information included in a random access response which the base station device transmits in response to the transmitted random access preamble. In an uplink synchronous status, upon receiving the random access response including timing deviation information, the mobile station device ignores the timing deviation information. Otherwise, the mobile station device performs the uplink timing alignment based on the timing deviation information.

Abstract: A system and method are provided for determining a time for safely sampling a signal of a dock domain. In one embodiment, a frequency estimate of a first clock domain is calculated utilizing a frequency estimator. Additionally, a time during which a signal from the first clock domain is unchanging is determined such that the signal is capable of being safely sampled by a second clock domain, using the frequency estimate. In another embodiment, a frequency estimate of a first dock domain is calculated utilizing a frequency estimator. Further, a phase estimate of the first clock domain is calculated based on the frequency estimate, utilizing a phase estimator. Moreover, a time during which a signal from the first clock domain is unchanging is determined such that the signal is capable of being safely sampled by a second clock domain, using the phase estimate.

Abstract: A communication system includes a first communication device and a second communication device that performs power line communication with the first communication device via an electric power line, wherein the first communication device transmits a plurality of times an initial packet signal added with an error detection code in each of reference timing at regular intervals in the vicinity of zero crossing timing. The second communication device determines whether a reception state is good or poor based on a result of the error detection on each of the received initial packet signals, and when the reception state is poor, the second communication device transmits an ACK signal in timing shifted by micro time from the reference timing after receiving the initial packet signal. Then, the first communication device transmits a data packet signal in timing at the regular interval after the timing of receiving the ACK signal.

Abstract: A communication system includes a first communication device and a second communication device that performs power line communication with the first communication device via an electric power line, wherein the first communication device transmits an initial packet signal added with an error detection code in each zero crossing period including zero crossing timing while changing transmission timing within the zero crossing period. The second communication device specifies optimum communication timing out of a plurality of pieces of transmission timing within the zero crossing periods based on a result of error detection on each initial packet signal, and transmits an ACK signal including timing information on the optimum communication timing. Then, the first communication device transmits a data packet signal in the optimum communication timing within the zero crossing period, which is specified based on the timing information.

Abstract: A data processing device includes a clock converter, a data converter, and an error detector. The clock converter is configured to receive a first clock signal, convert the first clock signal into a second clock signal, and output the second clock signal. The data converter is configured to receive first data, convert the first data into second data using the second clock signal, and output the second data. The error detector is configured to check whether the first clock signal is in a first clock state or a second clock state upon the first data transitioning to a first data state, and output an enable signal to the clock converter upon determining that the first clock signal has transitioned to the first clock state from the second clock state.

Abstract: A wireless transmission system includes: a communication unit for transmission; and a communication unit for reception. The communication units for transmission and reception are housed in a housing of the same electronic apparatus, or the communication unit for transmission is housed in a housing of first electronic apparatus and the communication unit for reception is housed in a housing of second electronic apparatus and a wireless signal transmission path enabling wireless information transmission between the communication units is formed between the communication units when the first and the second electronic apparatus are disposed at given positions to be integrated with each other. The communication unit for transmission includes a first carrier signal generating unit and a first frequency converter, and the communication unit for reception includes a second carrier signal generating unit, and a second frequency converter.

Abstract: There is provided a signal transmission device including a first communication module including a first signal transmission unit for transmitting a first transmission signal having first amplitude to a second communication module through a predetermined transmission path, and the second communication module including a second signal transmission unit for transmitting a second transmission signal having second amplitude different from the first amplitude to the first communication module through the predetermined transmission path, and a transmission timing adjustment unit for adjusting a transmission timing of the second transmission signal by the second signal transmission unit so that a transition timing of the first transmission signal transmitted from the first communication module and a transition timing of the second transmission signal coincide with each other at a receiving end of the first communication module.

Abstract: A method, an apparatus, and a system are provided in various embodiments of the present invention. According to embodiments of the present invention, the receiver samples the frequency signal from the transmitter to obtain sampling data and obtain the feedback IQ signal from the sampling data, and performs signal correction by using the feedback IQ signal. Sampling the received radio frequency signal does not need an additional component. The receiving channel installed in the receiver can be used to receive the radio frequency signal, which reduces the cost and power consumption.

Abstract: Spatial discrimination information is fed back at both the multi-antenna transmitter and the multi-antenna receiver connecting a UE and cells within a CoMP measurement set. With the UE feeding back the transmitter and the receiver side spatial discrimination information of each cell-to-UE connection, the composite spatial CSI over multiple sites/nodes can be determined. The approach is applicable for UEs with single or multiple receiving antennas, and the spatial discrimination information can be wideband long-term or subband short-term. In some embodiments, the spatial discrimination information at the receiver side is derived from the actual spatial channel while receiver implementation is taken into account. The spatial discrimination information at the transmitter and at the receiver can be fed back using codebooks for MIMO precoding.

Abstract: A communications device includes a baseband input to receive a baseband signal. A transmitter is coupled to the baseband input and generates a transmit signal based upon the baseband signal, the transmit signal having an initial transmit impairment. An auxiliary receiver is coupled to the transmitter and generates a receive signal having a receive impairment therein resulting from the initial transmit impairment. A controller determines a power of the baseband signal by integrating a product of the receive signal and a complex conjugate of the baseband signal, and determines a power of the receive signal by integrating a product of the baseband signal and the receive signal. The controller also determines the initial transmit impairment based upon the power of the baseband signal and the receive signal, and generates a transmit impairment compensation signal based upon the initial transmit impairment.

Abstract: A closed-loop antenna switching method, a reference signal allocating method, and a feedback signal transmitting method for the same are disclosed. Namely, by transmitting a reference signal via the plurality of transmitting antennas via the antenna switching for reference signal transmission for each prescribed multiple period of an antenna selection period, efficient antenna index information can be fed back. By setting an antenna switching period to a prescribed multiple of an antenna selection period, it is able to prevent power loss and data decoding performance degradation. And, the present invention includes transmitting a sounding reference signal (SRS) for each band selection period via at least one of the plurality of transmitting antennas and transmitting at least one data demodulation reference signal (DMRS) between the band selection periods via an antenna for not transmitting data by reference signal transmission antenna switching.

Abstract: A logic signal isolator comprising a transformer having a primary winding and a secondary winding; a transmitter circuit which drives said primary winding in response to a received logic signal, such that in response to a first type of edge in the logic signal, a signal of a first predetermined type is supplied to the primary winding and in response to a second type of edge in the logic signal, a signal of a second predetermined type is supplied to said primary winding, the primary winding and the transmitter being referenced to a first ground; and the secondary winding being referenced to a second ground which is galvanically isolated from the first ground and said secondary winding supplying to a receiver circuit signals received in correspondence to the signals provided to the primary winding, the receiver reconstructing the received logic signal from the received signals.

Abstract: A method of and apparatus for synchronous data transfer are described. The method may include encoding a clock period and data into an encoded signal, transmitting the encoded signal from a master device to a slave device, and recovering the data at the slave device without using a local oscillator. The apparatus may comprise a first integrated circuit including a master device configured to transmit an encoded signal of a clock period and data on a first port, and a second integrated circuit including a slave device where the slave device is configured to receive the encoded signal on a second port coupled to the first port and to recover the data without using a local oscillator.

Abstract: A base station initializes pseudo-random sequence generators on which wireless devices base generation of uplink reference signals. The base station determines a first sequence from a first subset of possible initialization sequences for a sequence generator of a first device, and determines a second sequence from a second subset of possible initialization sequences for a sequence generator of a second device. The range of this second subset spans at least the range of the first subset. The base station further encodes the first sequence as a first set of two or more parameters, and encodes the second sequence as a second set of one or more parameters. This second set includes at least one parameter not included in the first set, and comprises fewer bits than the first set. The base station initializes the sequence generators by transmitting the first and second sets of parameters to the devices.

Abstract: A clock data recovery circuit (CDR) extracts bit data values from a serial bit stream without reference to a transmitter clock. A controllable oscillator produces a regenerated clock signal controlled to match the frequency and phase of transitions between bits and the serial data is sampled at an optimal phase. A phase detector generates early-or-late indication bits for clock versus data transition times, which are accumulated and applied to a second order feedback control with two distinct feedback paths for frequency and phase, combined for correcting the controllable oscillator, selecting a sub-phase and/or determining an optimal phase at which the bit stream data values are sampled. The second order filter is operated at distinct rates such that the phase correction has a latency as short as one clock cycle and the frequency correction latency occurs over plural cycles.

Abstract: Methods and systems for detecting a preamble of a data packet in wireless communication systems is provided. To determine a preamble from a received signal, which may include a noise-altered preamble bit sequence, linear feedback shift registers (LFSRs) can be used to generate a count of the received preamble, and the count is compared to pre-generated scores to identify a match. Example methods include for each of a number of different preamble orientations of a preamble, generating a count value based on a comparison of bits of the preamble with a random bit sequence to produce a sequence of count values, and comparing the sequence of count values with m sequences of count values. A sequence of count values is identified that includes a maximum number of matching elements, and the received preamble is determined to be one of the m preambles corresponding to the identified sequence.

Abstract: Disclosed are a feedback-transmitting method and data-transmitting method, and a method for generating a codebook that can be used in a system such as LTE-A. When multiple base stations operate in a cooperative mode, using a codebook generated according to the present invention, an existing codebook for single cell transmission can be used to generate a codebook for cooperative transmission.

Abstract: A complex acquisition system and method for synchronizing components thereof. The complex acquisition system further including a master acquisition module. The master acquisition module further including an analog to digital acquisition signal generator for generating an analog to digital acquisition signal, a memory acquisition signal generator for generating a memory acquisition signal, a delay calibration signal for generating a delay calibration signal, a step source signal generator for generating a step source signal, and a synchronization module. The complex acquisition system further includes a plurality of slave acquisition modules, each also including a synchronization module. The complex acquisition system additionally includes a distribution system for distributing each of the analog to digital acquisition signal, memory acquisition signal, delay calibration signal and step source signal to each of the synchronization modules in the master and plurality of slave acquisition modules.

Abstract: A complex acquisition system and method for synchronizing components thereof. The complex acquisition system further including a master acquisition module. The master acquisition module further including an analog to digital acquisition signal generator for generating an analog to digital acquisition signal, a memory acquisition signal generator for generating a memory acquisition signal, a delay calibration signal for generating a delay calibration signal, a step source signal generator for generating a step source signal, and a synchronization module. The complex acquisition system further includes a plurality of slave acquisition modules, each also including a synchronization module. The complex acquisition system additionally includes a distribution system for distributing each of the analog to digital acquisition signal, memory acquisition signal, delay calibration signal and step source signal to each of the synchronization modules in the master and plurality of slave acquisition modules.

Abstract: Transmitters for data communication can include a pattern generator configured to generate parallel data stream composed of k bits, k being a natural number greater than 2, a serializer configured to convert the parallel data stream into a serial data stream, a pre-emphasis circuit configured to pre-emphasize the serial data stream based on a pre-emphasis control value, to transmit the pre-emphasized serial data stream to a receiver via a first transmission line, and a pre-emphasis controller configured to receive measured values of transmission errors of the pre-emphasized serial data stream from the receiver via a second transmission line, and configured to set the pre-emphasis control value corresponding to a minimum measured value of the transmission errors, to an optimum pre-emphasis control value.

Abstract: A clock and data recovery circuit is disclosed. The clock and data recovery circuit in accordance with an embodiment of the present invention uses a hybrid phase detector that is constituted by including a linear phase detector and a binary phase detector. Since the clock and data recovery circuit basically is constituted with the linear phase detector, a charge pump, a loop filter, a voltage controlled oscillator and a D flip flop to recover clock and data, a phase detector gain is irrelevant to the jitter of received data and recovered clock, and it is possible to make a fine adjustment of the size of up/down currents of the charge pump using the binary phase detector and a charge pump controller, thereby compensating a phase offset between the received data and the recovered clock.

Abstract: A method, a system, and an apparatus for dynamically adjusting a link, where the method includes: determining, by a transmitting end, link adjustment information according to the data traffic change when detecting a change of data traffic, where the link adjustment information contains the number of required working links; and adjusting, by the transmitting end, the number of working links on an interface of the transmitting end according to the determined link adjustment information, and sending a configuration request to a receiving end, where the configuration request includes the link adjustment information; and after receiving the configuration request, adjusting, by the receiving end, the number of working links on an interface of the receiving end according to the configuration request. In the embodiments of the present invention, data transmission on an original working link is not affected, thereby saving bandwidth and power consumption.

Abstract: A wireless communications device may include a portable housing and a temperature-compensated clock circuit carried by the portable housing. The device may further include a wireless receiver carried by the portable housing for receiving timing signals, when available, from a wireless network, and a satellite positioning clock circuit carried by the portable housing. A clock correction circuit may be carried by the portable housing for correcting the temperature-compensated clock circuit based upon timing signals from the wireless network when available, and storing historical correction values for corresponding temperatures. The clock correction circuit may also correct the temperature-compensated clock circuit based upon the stored historical correction values when timing signals are unavailable from the wireless network, and correct the satellite positioning clock based upon the temperature-compensated clock circuit.

Abstract: A device comprises a transmitter, a receiver and a clock generator that generates a clock signal having a local clock phase. A clock recovery circuit communicates with the receiver and recovers a host clock frequency from data received from a host by the receiver. A frequency offset circuit communicates with the clock recovery circuit and the clock generator and generates a frequency offset based on the local clock phase and the recovered host clock frequency. A frequency compensator compensates a frequency of the transmitter using the frequency offset.

Abstract: Precoder weights employed at a base station which coordinates with other base stations to form a super-cell are determined by: (a) determining an initial downlink precoding matrix at the base station for a mobile station serviced by the base station in the super-cell; (b) revising a downlink receiver matrix associated with the mobile station based on the initial downlink precoding matrix; (c) transforming the downlink receiver matrix to an uplink precoder matrix associated with the mobile station; (d) revising an uplink receiver matrix associated with each base station in uplink communication with the mobile station based on the uplink precoder matrix associated with the mobile station; and (e) revising the initial downlink precoding matrix by transforming the uplink receiver matrix to a revised downlink precoding matrix. Steps (b), (c), (d) and (e) are repeated for a particular number of iterations to determine a final downlink precoding matrix for the mobile station.

Abstract: Assuring acquisition of symbol timing in a full-duplex data transceiver under inter-symbol interference conditions. One embodiment includes a transmitter comprising a first local clock having a first free running frequency, and a receiver comprising a second local clock having a second frequency initially set to a value higher than the first free running frequency. A first type decision-directed timing recovery mechanism is intentionally limited to only decreasing the frequency of the second local clock. A second type decision-directed timing recovery mechanism is not limited to only decreasing the frequency. The receiver receives symbols, decrease the frequency of the second local clock to a third frequency value using the first type decision-directed timing recovery mechanism, disables the first type mechanism after reaching the third frequency, and then phase-lock the second local clock to the optimal phase under MMSE criteria using the second type decision-directed timing recovery mechanism.

Abstract: Systems and methodologies are described that facilitate encoding feedback or control information into a compact payload. In particular, a rank indicator, a precoding matrix indicator and channel quality indicators are packaged into a control channel payload that fits into a single sub-frame. The payload format is determined based at least in part on an antenna configuration or channel quality indicator granularity. In addition, hybrid automatic repeat requests can be included in the payload.

Abstract: Disclosed are various embodiments for dividing workload in a digital signal processing system. In one embodiment, the system includes at least one analog-to-digital converter configured to receive a three phase analog waveform and a digital waveform. The system can also include a first DSP configured to interface with an external computer and a second DSP configured to receive the digital waveform and isolate a specified frequency range. The system can also include a plurality of DSP's configured to extract specified channels from the specified frequency range and output the extracted channel data.

Abstract: Methods, systems, and devices are described for estimating a frequency response using a received signal. A first spectral estimation is performed on a digitized representation of an initial version of a wireless signal. A second spectral estimation is performed on the digitized representation of the wireless signal as received from the transmitter. The first spectral estimation is compared with the second spectral estimation to estimate a frequency response. A later signal transmitted from the transmitter may be pre-distorted to compensate for the estimated frequency response. The disclosed frequency response estimation techniques may be used in a satellite communications system.

Abstract: A transceiver configured to be implemented in a first device includes transmitter and receiver modules and first and second estimator modules. The receiver module receives a first signal transmitted on a channel from a second device to the first device. The first estimator module estimates a first parameter associated with the first signal or the channel. The second estimator module estimates a carrier frequency offset based on the first parameter. The carrier frequency offset is a difference between a first carrier frequency of the first device, and a second carrier frequency of the second device. The transmitter module adjusts a second parameter based on the carrier frequency offset, and based on the second parameter, transmits a second signal to the second device or the receiver module adjusts a third parameter based on the carrier frequency offset, and based on the third parameter, receives a third signal from the second device.

Abstract: In described embodiments, a transceiver includes a clock and data recovery module (CDR) with an eye monitor and a cycle slip monitor. The cycle slip detector monitors a CDR lock condition, which might be through detection of slips in sampling and/or transition timing detection. The cycle slip detector provides a check point to sense system divergence, allowing for a mechanism to recover CDR lock. In addition, when the CDR is out-of-lock, the various parameters that are adaptively set (e.g., equalizer parameters) might be invalid during system divergence. Consequently, these parameters might be declared invalid by the system and not used.

Abstract: Apparatus and method are presented for measuring the transmitter and antenna system time delay (TAD) of the cadence sync at the input of a conventional 8 VSB data processing system until the emission of the segment sync of the corresponding data frame sync data segment. This includes sequentially conditioning a multi-bit input digital signal containing an initial cadence sync, inserting data patterns into the digital signal, inserting a known data pattern into the data frame at a known position of the data frame and receiving the cadence sync and the known pattern and measuring the time delay therebetween.

Abstract: A data reception unit 21 of a reception device 20n receives calibration data to detect a data reception state or a clock reception state in the reception device 20n from a data transmission unit 11 of a transmission device 10. A decoder unit 24 causes a transmission unit 26 to send out calibration sample data that a sampler unit 23 obtained by sampling calibration data to the transmission device 10. A control unit 15 of the transmission device 10 detects a data reception state or a clock reception state in the reception device 20n based on calibration sample data received from the reception device 20n and controls the data transmission unit 11 and a clock transmission unit 12 based on the detection result.

Abstract: Provided are a fixed station receiver for a Multi-Input Multi-Output (MIMO) communication system and an uplink adaptation method thereof. In the uplink adaptation method, a sounding reference signal (SRS) is received from a terminal including a plurality of transmission antennas. A complex channel matrix (H) corresponding to a channel response and a noise variance (?2) corresponding to a noise power is calculated from the sounding reference signal. A signal-to-interference and noise ratio (SINR) on each transmission symbol is calculated with reference to the complex channel matrix (H) and the noise variance (?2). A pre-coding matrix of the terminal is selected with reference to the signal-to-interference and noise ratio (SINR).

Abstract: The present invention is related to a method and apparatus for implementing space frequency block coding (SFBC) in an orthogonal frequency division multiplexing (OFDM) wireless communication system. The present invention is applicable to both a closed loop mode and an open loop mode. In the closed loop mode, power loading and eigen-beamforming are performed based on channel state information (CSI). A channel coded data stream is multiplexed into two or more data streams. Power loading is performed based on the CSI on each of the multiplexed data streams. SFBC encoding is performed on the data streams for each of the paired subcarriers. Then, eigen-beamforming is performed based on the CSI to distribute eigenbeams to multiple transmit antennas. The power loading may be performed on two or more SFBC encoding blocks or on each eigenmodes. Additionally, the power loading may be performed across subcarriers or subcarrier groups for weak eigenmodes.

Abstract: A transceiver system is disclosed that includes a plurality of transceiver chips. Each transceiver chip includes one or more SERDES cores. Each SERDES core includes one or more SERDES lanes. Each SERDES lane includes a receive channel and a transmit channel. The transmit channel of each SERDES lane is phase-locked with a corresponding receive channel. The transceiver system has the capability of phase-locking a transmit clock signal phase of a transmitting component with a receive clock signal phase of a receiving component that is a part of a different SERDES lane, a different SERDES core, a different substrate, or even a different board. Each SERDES core receives and transmits data to and from external components connected to the SERDES core, such as hard disk drives. A method of transferring data from a first external component coupled to a receive channel to a second external component coupled to a transmit channel is also disclosed.

Abstract: In a wireless network, plural downlink signals from plural base stations are transmitted to a terminal. The plural downlink signals all carry the same information to the terminal. The terminal provides feedback on the downlink channels. The feedback provides information on the taps of the channels. The amount of information fed back is constrained. Based on the feedback, transmission parameters of the downlink signals are adjusted. The process of transmitting, providing feedback, and adjusting the parameters continue so that the energy of the downlink signal is enhanced at the terminal location and suppressed elsewhere. Beam forming can be used to further suppress the energy signature at locations other than the terminal location.

Abstract: A radio communication apparatus and an associated method are provided. The apparatus includes a receiving unit configured to receive first data and second data, which are transmitted from a plurality of antennas for spatial-multiplexing using a plurality of blocks, into which a plurality of consecutive subcarriers in a frequency domain are divided. The apparatus further includes a calculating unit configured to calculate a first absolute CQI value per each of the blocks for the first data and a second absolute CQI value per each of the blocks for the second data, and calculate a relative value of the second absolute CQI value with respect to the first absolute CQI value, per each of the blocks. The apparatus still further includes a transmitting unit configured to transmit the first absolute CQI value and the relative value of the second absolute CQI value in the same block.

Abstract: A method and apparatus of transmitting a reference signal in a wireless communication system is provided. The method includes generating a precoded reference signal or a non-precoded reference signal in accordance with a rank, and transmitting the generated reference signal. Uplink transmission using multiple transmit antennas is supported through reference signal design and related control signaling.

Abstract: A radio apparatus includes: first and second reception units to receive first and second signals from first and second radio apparatus controllers, respectively; first and second synchronous clock generation units to generate first and second recovery clocks from clock components included in the first and second signals received by the reception units, respectively; a clock synchronization detection unit to detect whether or not the second recovery clock is synchronous with the first recovery clock; a code selection unit to select a code indicating the synchronous state according to a detection result of the synchronization detection unit; a signal processing unit of generate a third signal to which the code selected by the code selection unit is added and which is synchronous with the first recovery clock; and a transmission unit to transmit the third signal generated by the signal processing unit to the second radio apparatus controller.

Abstract: Embodiments of the present invention set forth a method and system for reducing uncertainty in receive and transmit timestamps created by an NTP server. The uncertainty in the receive timestamps is removed by recording the time-of-arrival in the hardware clock of the NTP server before the incoming packets may be delayed by traversing the various layers of software in a timestamping system. The uncertainty in the transmit timestamps is removed by giving the outgoing packets a timestamp in the future using an estimate of the transmission latency calculated by the latency estimator filter. Subsequently, the actual time-of-departure is used to re-calculate and update the estimate of the transmission latency. In this fashion, superior control of the timestamping function may be implemented in existing NTP servers in a manner that retains interworking compatibility with the current NTP standards.

Abstract: The radio communication apparatus includes two or more antennas, a receiving unit for receiving a notice signal from a communication partner, two or more units for changing the number of data sequences and for coupling to the antennas according to two or more transmitting methods out of a MIMO multiplexing method, a MIMO diversity method, and an adaptive array antenna method, a selecting unit for selecting at least one out of the two or more units based on the notice signal, and a transmitting unit for notifying the communication partner of the transmission method corresponding to the selected unit.

Abstract: An efficient low latency buffer, and method of operation, is described. The efficient low latency buffer may be used as a bi-directional memory buffer in an audio playback device to buffer both output and input data. An application processor coupled to the bi-directional memory buffer is responsive to an indication to write data to the bi-directional memory buffer reads a defined size of input data from the bi-directional memory buffer. The input data read from the bi-directional memory buffer is replaced with output data of the defined size. In response to a mode-change signal, the defined size of data is changed that is read and written from and to the bi-directional memory buffer. The buffer may allow the application processor to enter a low-powered sleep mode more frequently.

Abstract: System for measuring satellite downlink amplifier linearity includes a pulsed signal generator for selectively generating low duty cycle pulses. A linear transmitter uplink amplifier is provided for amplifying the low duty cycle pulses and generating an uplink signal. An antenna transmits the amplified uplink signal to an orbiting satellite. A downlink amplifier in the satellite generates a downlink signal for re-transmission to an Earth-based antenna. A pulse receiver is provided for receiving the downlink signal and providing information regarding the transfer function of the downlink amplifier. Preferably, a delayed trigger circuit is coupled to the pulse signal generator for activating the pulsed signal generator after a time delay substantially corresponding to the propagation times of the uplink and downlink signals.

Abstract: A method for receiver state estimation includes communicating, from a first communications device to a second communications device, a first plurality of wake-up frames; receiving, at the first communications device from the second communications device, an indication of a received wake-up frame of the communicated first plurality of wake-up frames; determining, by the first communications device, a time at which the second communications device is in a ready state based on the received indication; subsequently communicating, from the first communications device to the second communications device, a second plurality of wake-up frames. The first plurality is greater than the second plurality, the reduction in number from the first plurality to the second plurality being based on the determined time at which the second communications device is in a ready state.

Abstract: A method for relaying and forwarding feedback information in hybrid automatic repeat request scenario is provided, wherein the method for sending feedback information includes that: a relay station receives a resource allocation message; the relay station determines the time of sending the feedback information according to the resource allocation message, and sends the corresponding feedback information when the feedback time arrives. The processes of triggering the relay station to perform feedback or sending in multiple HARQ scenarios such as initial transmission and retransmission of downlink and uplink, and uplink feedback loss of subordinate node etc. are integrally and uniformly defined according to the present invention.

Abstract: In order to transmit a large amount of data in series at a time with a MIMO communication scheme while avoiding deterioration of decoding characteristics due to change over time by a channel matrix, a wireless communication system uses an open-loop type and a closed-loop type of MIMO communication modes in combination and switches to the open-loop MIMO communication mode in response to the information that the amount of data to be transmitted at a time has exceeded a predetermined amount of bits or a predetermined transmission time during data transmission under the closed-loop MIMO communication mode. By discontinuing useless closed-loop MIMO communication and switching to the open-loop MIMO communication mode that is better than Zero-forcing, the decoding characteristics are prevented from simply becoming deteriorated.