Abstract: The receiver (1) picks up low rate FSK radio frequency signals. This receiver includes an antenna (2) for receiving FSK radio frequency signals, a low noise amplifier (3) connected to the antenna, a local oscillator (7) for supplying oscillating signals (LO), a phase shift circuit (16) for performing a 0° to 90° phase shift, and vice versa, in the oscillating signals (LO) or the incoming FSK radio frequency signals in each semi-period of a phase switching cycle (1/fs). The phase shift circuit alternately and successively generates in-phase and quadrature oscillating signals, or in-phase and quadrature incoming FSK radio frequency signals. The receiver includes a single mixer (4) for mixing the oscillating signals successively with the incoming FSK radio frequency signals, so as to generate alternately intermediate in-phase and quadrature baseband signals (INT) as a function of the phase shift circuit.

Abstract: A receiver is an ATSC (Advanced Television Systems Committee)-receiver and comprises a staggered quadrature amplitude modulator for providing an staggered quadrature amplitude modulated (SQAM) signal from a received signal; an equalizer and a data-aided symbol timing recovery (STR) loop. The equalizer operates outside of the data-aided symbol timing recover loop.

Abstract: Aspects of the disclosure provide methods and apparatuses that use counter based phase signaling to transmit digital data. The counter based phase signaling uses a reduced number of transitions to transmit a large number of bits. A method of counter based phase signaling includes transmitting a reference transition to start multiple-bit data block transmissions from a transmitter module to a receiver module, starting a first counter to count in accordance with a first clock of the transmitter module, and transmitting a first data transition corresponding to transmitting a first multiple-bit data block from the transmitter module to the receiver module when a counted number by the first counter corresponds to the first multiple-bit data block. The first clock has a same frequency as a second clock in the receiver module.

Abstract: A method for packing data over a power line communication channel is disclosed herein. The method comprises packing data into symbol body, adding a first pad in front of the symbol body to form a full symbol and determining the time instance in which the peak absolute voltage point of the AC electric power occurs. And subsequently it is to send the full symbol through the power line in a manner synchronized with the time instance aforesaid. Based on the interference condition detection, the invention allows receiver side adaptation.

Abstract: A network includes a transmitter and a receiver, wherein the transmitter includes a set of transmit antennas and the receiver includes a set of receive antennas. The transmitter duplicates a packet as copies of the packet, and selects subsets of the set of transmit antennas independent of channel characteristics between the subsets of transmit antennas and the set of receive antennas, wherein combinations of the antennas in the subsets of the transmit antennas are different. The receiver selects subsets of the set of receive antennas independent of channel characteristics between the subsets of receive antennas and the set of transmit antennas, wherein combinations of the antennas in the subsets of the receive antennas are different. The selected subsets are used to transmit the packet, and retransmit the packet in case of a failure in a previous transmission.

Abstract: In a method for generating a physical layer (PHY) data unit for transmission via a communication channel, a first set of modulation coding schemes (MCSs) and a second set of MCSs that correspond to a number of spatial streams and a number of encoders are provided. The first set of MCSs correspond to a first channel bandwidth and the second set of MCSs correspond to a second channel bandwidth, and the first set of MCSs is different than the second set of MCSs. An MCS is selected from the first set of MCSs when the PHY data unit is to be transmitted using a channel having the first channel bandwidth, and the MCS is selected from the second set of MCSs when the PHY data unit is to be transmitted using a channel having the second channel bandwidth. Information bits are encoded using the number of encoders and according to the selected MCS, and the encoded information bits are parsed into the number of spatial streams.

Abstract: An adjacent channel interference rejection mechanism is provided to detect and reject CCK-modulated signals from an adjacent channel in a wireless communication receiver. Replicas of the baseband signals are frequency-shifted and then analyzed through a series of correlations to compare the power of the correlation outputs. An adjacent channel interference of a CCK-modulated signal is determined and rejected based on the comparisons meeting a predetermined tolerance level.

Abstract: Data receivers often include equalizers for operating on received signals. The equalizers often have a plurality of taps, with signals from each tap weighted based on tap settings or values. The tap settings may be set based on bit error rates of data output from the equalizer. In some embodiments data output from the equalizer is split into two signals, and the two signals are processed to indicate a data eye of the data output from the equalizer. Preferred tap settings may be determined by setting tap settings to different values and using tap settings expected to maximize the data eye. This may be performed separately for different bit settings in an attempt to reduce effects of inter-signal interference.

Abstract: The present invention relates to data processing techniques in multi-channel data transmission systems. In this invention, a novel approach is proposed to deal with FEXT interferences in the application of high/ultra-high speed Ethernet systems. Compared with the traditional FEXT cancellation approaches, the proposed FEXT canceller can deal with the non-causal part of FEXT, and thus can achieve better cancellation performance. Instead of using the conventional DFE, structure, TH precoding technique is incorporated into the proposed design to alleviate the error propagation problem. The resulting FEXT cancellers do not contain feedback loops which makes the high speed VLSI implementation easy. A modified design is also developed by using a finite signal as the input to the FEXT canceller such that the hardware complexity of the proposed FEXT canceller can be reduced.

Abstract: The present invention relates to a method and apparatus for code acquisition. The present invention performs variable delay correlation to obtain the peak correlation result which is immune to carrier frequency offset and Doppler. The present invention makes use of a mapping parameter which is immune to sampling frequency offset. In particular, the present invention is applicable to the DTMB standard.

Abstract: A novel and useful multi-antenna receiver that receives, demodulates and decodes a broadcast signal, whose modulation and encoding of time and timing information allow for reliable and power-efficient operation. The multi-antenna receiver of the present invention is adapted to eliminate or substantially reduce the reception nulls that occur in receivers having a single antenna that is placed in a fixed position. Two or more antennas are employed whereby the receiver generates a combined signal based on a combination of the individual antenna signals or selects one of the antenna signals for input to the receiver based on desired criteria such as signal-to-noise-and-interference-ratio (SNIR). This results in greater robustness of the communication link by reducing or eliminating reception nulls and by rejecting interference through the selection of the antenna for which the signal-to-interference ratio is higher.

Abstract: Varying embodiments of the present invention describe a closed loop system for processing the beamforming information, qualifying the expected performance, activating and deactivating the beamforming system. A first embodiment is a method for closed loop beamforming in a wireless communication system, the system comprising a transmitter and a receiver, the method comprising initiating beamforming on a communication channel between the transmitter and the receiver, monitoring the communication channel, periodically determining a condition of the communication channel and controlling beamforming based on the condition of the communication channel.

Abstract: In a method for recovery of a dock from a received digital data stream and an apparatus for recovering a clock from a received digital data stream, phase-shifted dock signals are generated from a receiver's dock. After selecting one of the phase-shifted clock signals, two other phase-shifted clock signals are determined. Depending on sample values taken at rising/falling edges of the three selected phase-shifted clock signals, counter values are increased and compared. The selection of phase-shifted clock signals and the steps of sampling the input digital data stream, comparing the values and increasing counter values, if required, are repeatedly performed until the comparison result of the counter values indicates that one of the latter determined phase-shifted clock signals strobes the received digital data stream in the center of a bit period.

Abstract: Methods and apparatus for processing multichannel signals in a multichannel receiver are described. In one implementation, a plurality of demodulator circuits may provide a plurality of outputs to a processing module, with the processing module then simultaneously estimating noise characteristics based on the plurality of outputs and generating a common noise estimate based on the plurality of outputs. This common noise estimate may then be provided back the demodulators and used to adjust the demodulation of signals in the plurality of demodulators to improve phase noise performance.

Abstract: In a method for generating a physical layer (PHY) data unit for transmission via a communication channel, a first set of modulation coding schemes (MCSs) and a second set of MCSs that correspond to a number of spatial streams and a number of encoders are provided. The first set of MCSs correspond to a first channel bandwidth and the second set of MCSs correspond to a second channel bandwidth, and the first set of MCSs is different than the second set of MCSs. An MCS is selected from the first set of MCSs when the PHY data unit is to be transmitted using a channel having the first channel bandwidth, and the MCS is selected from the second set of MCSs when the PHY data unit is to be transmitted using a channel having the second channel bandwidth. Information bits are encoded using the number of encoders and according to the selected MCS, and the encoded information bits are parsed into the number of spatial streams.

Abstract: Joint transmit error (i.e., carrier leak and I/Q mismatch) calibration can be implemented in a transmitter unit in a wireless device. DC signals can be superposed onto digital complex tone signals to generate calibration signals for joint transmit error calibration. The calibration signals may also be phase shifted and/or pre-distorted with digital I/Q phase to yield distinct calibration measurements that can be used for joint transmit error calibration. Digital scaling can be applied at the transmitter unit in accordance with a transmitter gain setting to maintain a constant receiver gain setting. At a receiver unit of the wireless device, the DC signals can be separated from the digital complex tone signals for transmit error calibration. Such a joint transmit error calibration can minimize calibration time, reduce the number of computations required for transmit error calibration, improve the accuracy of the transmit error calibration, and improve performance of the wireless device.

Abstract: Systems, methods, and circuits provide phase inversion of a clock signal. A first clock signal is received. A phase inversion signal indicates the existence of a 180 degree phase difference between the first clock signal and a second clock signal. As a result of the phase inversion signal indicating the 180 degree phase difference, the system, methods and circuits adapt the first clock signal by extending the first clock signal by a phase such that the first clock signal's rising edges and falling edges align with the second clock signal's rising edges and falling edges. As a result, the 180 degree phase difference between the clock signals is eliminated.

Abstract: A communication system includes a communication station that converts a value information into a code value based on a corresponding relationship in which a difference between a first value information and a second value information is set to any value equal to or greater than two, where the second value information corresponds to a code value where an error occurs in one bit of the code value corresponding to the first value information.

Abstract: A method and device for acquiring a precoding matrix are provided by the present invention. The method for acquiring a precoding matrix includes: for each receiving end, selecting the interference vectors as the interference space basis vectors from whole interference vectors, representing the remaining interference vectors as the linear combination of the interference space basis vectors, wherein the remaining interference vectors are the interference vectors in the whole interference vectors of the receiving end except the interference vectors which act as the interference space basis vectors (101); determining the currently used precoding matrix according to the linear combination of the interference space basis vectors represented by the remaining interference vectors of each receiving end and the current channel condition (102). The technical solution of the present invention can eliminate interference and do not generate Bit Error Rate (BER) floor.

Abstract: A transmitter and a receiver of a multiple input multiple output (MIMO) communication system may use two codebooks to share channel information. When the transmitter uses eight transmit antennas, two codebooks may be defined. When the receiver generates two precoding matrix indicators from two codebooks, a combination of the two precoding matrix indicators may indicate a single precoding matrix. Precoding matrix candidates may also be defined.