Disclosed are a method for multi-user transmission and reception in a wireless communication system and a device for same. More particularly, a method for performing multi-user (MU) transmission by a station (STA) device in a wireless communication system comprises the steps of: generating a high efficiency-long training field (HE-LTF) sequence in a frequency domain in accordance with an MU transmission bandwidth; and transmitting a physical protocol data unit (PPDU) which comprises one or more symbols to which the HE-LTF sequence is mapped, wherein the HE-LTF sequence can be generated by multiplying one row of a P matrix to a length unit of a row of the P matrix in a predetermined sequence.

A wireless communication device and method therein for time synchronization in a wireless communication network are disclosed. The wireless communication device determines a first timing (tc) by performing a coarse time synchronization based on a synchronization signal received by the wireless communication device, wherein the received synchronization signal is sampled either in an original sampling rate or a reduced sampling rate. The wireless communication device determines a second timing (tf) by performing a fine time synchronization based on the determined first timing (tc) and the to received synchronization signal.

A method and an apparatus determine a time of start of series of OFDM symbols forming an OFDM packet, wherein one or more symbols of the OFDM signal includes a plurality of copies of a short training sequence made of a plurality of time-domain samples. The method includes determining a coarse time index, determining a fine time index, and determining the time of start of each OFDM symbols based on the fine time index. The coarse time-domain sample of the coarse time index is within a coarse estimation error interval, and the time-domain samples of the coarse estimation error interval are converted into frequency domain samples. A metric value is determined for each frequency domain samples, and the fine time index is the time index corresponding to one of the coarse estimation error interval having its associated frequency domain sample having the lowest metric value.

A cable mode includes a processor configured to receive fractional OFDM offset frequency spacing parameter and locations of CWT tone signals relative to locations of scattered pilot signals across an OFDM channel. The processor inserts pairs of CWT tone signals relative to the locations of the scattered pilot signals. The CWT tone signals are offset from each of the scattered pilot signals by a positive offset frequency and a negative offset frequency based on the fractional OFDM offset frequency spacing parameters. The CWT tone signals are transmitted in an upstream full duplex (FDX) subband. The CWT tone signals are processed to determine an average value of a Receive Modulation Error Ratio (RxMER) over a period of time in order to determine assigns of cable modems to interference groups.

A processor-implemented method includes receiving a signal representing a first encoded data and calculating an estimated timing offset and/or an estimated frequency offset associated with the signal. A correction of at least one of a timing offset or a frequency offset of the signal is performed based on the estimated timing offset and/or the estimated frequency offset, to produce a modified signal. An effective channel is subsequently detected based on the signal or the modified signal. A second encoded data is generated based on the modified signal, a known vector, at least one left singular vector of the effective channel, and at least one right singular vector of the effective channel. A signal representing the second encoded data is transmitted to a communication device for identification of contents of a message at a different processor.

A transmitter for transmitting data to communications devices via a wireless access. The transmitter including modulator circuitry configured to receive modulation symbols of a segment and to rotate each modulation symbol by an angle dependent on a choice of modulation scheme, and receive each of the segments of rotated modulation symbols and for each segment to separate real and imaginary components of the rotated modulation symbols for the segment and to interleave the real components of the rotated modulation symbols of the segment differently to the imaginary components of the rotated modulation symbols of the segment. The circuitry also is configured to recombine the real and imaginary interleaved components of the rotated modulation symbols of each segment and to form from the real and imaginary components modulation cells.

A receiver detects a received signal, transmitted by a transmitter to carry payload data as Orthogonal Frequency Division Multiplexed (OFDM) symbols in divided frames, each frame including a preamble including plural bootstrap OFDM symbols. A detector circuit detects, from the bootstrap OFDM symbols, a synchronization timing for converting a useful part of the bootstrap OFDM symbols into the frequency domain. A bootstrap processor detects an estimate of the channel transfer function from a first OFDM symbol, and a demodulator circuit recovers the signaling data from the bootstrap OFDM symbols using the estimate. The bootstrap processor includes an up-sampler configured to receive the bootstrap OFDM symbols, to form an up-sampled frequency domain version of the bootstrap OFDM symbol, and an output processor configured to identify a peak correlation result, to determine frequency offset of the received signal from a relative position of the peak correlation result in the frequency domain.

In one embodiment, an apparatus includes: a radio frequency (RF) front end circuit to receive and downconvert a RF signal to a second frequency signal, the RF signal comprising an orthogonal frequency division multiplexing (OFDM) transmission; a digitizer coupled to the RF front end circuit to digitize the second frequency signal to a digital signal; and a baseband processor coupled to the digitizer to process the digital signal. The baseband circuit comprises a first circuit having a first plurality of correlators having an irregular comb structure, each of the first plurality of correlators associated with a carrier frequency offset and to calculate a first correlation on a first portion of a preamble of the OFDM transmission.

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.

DM-RS symbols may be inserted in the beginning of a subframe, or in two parts of the subframe. In one aspect, a method, a computer-readable medium, and an apparatus for dynamically conveying DM-RS information are provided. The apparatus may be a base station. The apparatus may determine the number of DM-RS symbols and/or the locations within a subframe for transmission of the DM-RS symbols. The apparatus may transmit the number of the DM-RS symbols and/or the locations within the subframe for transmission of the DM-RS symbols to a UE. In another aspect, a UE may receive the number of DM-RS symbols and/or the locations within a subframe for transmission of the DM-RS symbols from a base station. The UE may decode the DM-RS symbols from the subframe based on the number of the DM-RS symbols and/or the locations within a subframe for transmission of the DM-RS symbols.