The present invention relates to a method and apparatus for channel estimation between a transmitter and a receiver in a wireless communications system. In one arrangement, the method comprises: receiving at the receiver a first sequence of bits representing a first sequence of coded symbols transmitted over the communications channel; decoding the first sequence of coded symbols using maximum-likelihood based decoding including: generating traceback outcomes by tracing backwards the first sequence of bits through a maximum-likelihood based traceback path, the traceback outcomes including a first portion associated with a first traceback depth and a second portion associated with a second traceback depth that is deeper than the first traceback depth; generating a channel estimate of the communications channel based on the first portion of the traceback outcomes; and generating an estimate of at least some information bits coded in the first sequence of coded symbols based on the second portion of the traceback outcomes.

The technology relates to bandwidth constrained communication systems with neural network based detection. In some embodiments, a bandwidth constrained equalized transport (BCET) communication system comprises: a transmitter comprising an error control code encoder, a pulse-shaping filter, and a first interleaver; a communication channel; and a receiver comprising a neural network processing block that processes a received signal. The error control code encoder can append redundant information onto the signal. The pulse-shaping filter can intentionally introduce memory into the signal in the form of inter-symbol interference. The first interleaver can change a temporal order of the symbols in the signal. The neural network can be trained with positive mappings between transmitted and decoded training signals, or negative mappings between training signals and erroneous decoded signals that are known to contain errors.

A receiver includes a decision feed forward equalization (DFFE) system that generates, based on a digital signal that includes at least one intersymbol interference (ISI) value introduced by a communication channel, a detected signal including a set of detected symbol values. The DFFE system cancels the at least one ISI value from the detected signal using the set of estimated transmitted symbols and a set of tap coefficients to obtain a compensated signal and a set of compensated symbol values.

Provided is a data transmitting and receiving apparatus that may process a signal to be transmitted using a faster-than-Nyquist (FTN) method. The data transmitting and receiving apparatus may perform low-density parity-check (LDPC) encoding on data to be transmitted using a first matrix having a first degree based on a preset reference and a second matrix having a single diagonal matrix structure, independently perform interleaving and symbol mapping on each of an information bit and a parity bit of the data, accelerate an output signal by a transmission rate based on the FTN method, and transmit the data.

A method includes: receiving a to-be-decoded symbol sequence, where the to-be-decoded symbol sequence includes N symbols; dividing the received to-be-decoded symbol sequence into a first symbol sequence and a second symbol sequence; calculating first distances between the first symbol sequence and each of corresponding 2.sup.K ideal superimposed symbol sequences, and obtaining paths corresponding to relatively small distances based on the first distances; sequentially performing sequence detection on each symbol in the second symbol sequence based on the paths corresponding to the 2.sup.k-1 relatively small distances, calculating second distances between each symbol in the second symbol sequence and each ideal symbol sequence, and after the sequence detection is performed on a last symbol, obtaining an ideal symbol sequence corresponding to a minimum distance based on the second distances; and using the ideal symbol sequence corresponding to the minimum distance as an output symbol sequence.

A broadcast transmitter and a method of processing broadcast data in the broadcast transmitter are disclosed. The method includes the steps of performing RS encoding and CRC encoding on mobile service data to build RS frames belonging to an ensemble, wherein each of the RS frames are mapped into data groups, wherein each of the data groups comprises known data sequences and a portion of FIC data including information for rapid mobile service acquisition, wherein the information for rapid mobile service acquisition includes transport stream identification information for identifying a mobile broadcast carrying a mobile service that includes the mobile service data and C/N indication information for indicating whether the FIC data are applicable to a current transmission frame or a next transmission frame, multiplexing data in the data groups and main service data, and transmitting a transmission frame including the multiplexed data.

The present disclosure provides techniques for bandwidth constrained communication systems with frequency domain information processing. A bandwidth constrained equalized transport (BCET) communication system can include a transmitter, a communication channel, and a receiver. The transmitter can include a pulse-shaping filter that intentionally introduces memory into a signal in the form of inter-symbol interference, an error control code (ECC) encoder, a multidimensional fast Fourier transform (FFT) processing block that processes the signal in the frequency domain, and a first interleaver. The receiver can include an information-retrieving equalizer, a deinterleaver with an ECC decoder, and a second interleaver joined in an iterative ECC decoding loop.

In some embodiments, a DFE including: an input terminal configured to receive an input signal carrying a plurality of symbols; an adder circuit coupled to the input terminal of the DFE; a plurality of comparator circuits configured to receive respective threshold signals; a plurality of slicer circuits coupled to respective comparator circuits of the plurality of comparator circuits; and a plurality of multiplier circuits coupled to respective slicer circuits of the plurality of slicer circuits, the plurality of multiplier circuits configured to multiply respective correction coefficients of a plurality of correction coefficients times respective outputs of respective slicer circuits to produce respective multiplication results of a plurality of multiplication results, where: the adder circuit is configured to subtract the plurality of multiplication results from the input signal, and the plurality of correction coefficients are independently adjusted based on a previously received symbol.

In a MIMO detector, a slicing list detection scheme employs a complex plane to represent symbols in an alphabet, in which all decision regions are bounded by either vertical lines or horizontal lines. A K-best scheme accesses the complex plane and an offline-generated lookup table to detect elements of a received vector. At each level, the system prunes all but the K-best candidates from each surviving node through the slicing list detector.

There is provided a decoder for decoding a data signal received through a transmission channel in a communication system, the decoder (310) comprising a symbol estimation unit (311) configured to determine estimated symbols representative of the transmitted symbols carried by the received signal, the estimated symbols being determined from nodes of a decoding tree based on a weight metric associated with each of the node. The decoder further comprises a termination alarm monitoring unit (312) for monitoring a termination alarm depending on the current decoding computation complexity, the termination alarm being associated with a metric parameter, the symbol estimation unit being configured to reduce the weight metric of each node of the decoding tree by a quantity corresponding to a function of the metric parameter associated with the termination alarm, in response to the triggering of the termination alarm.