Embodiment reduced-state trellis equalization techniques compute accumulated path metrics (APMs) for a subset of candidate states for at least some stages in the trellis based on a neighborhood map of an ML state. This reduces the number of APMs that are computed and stored during trellis equalization. Other embodiments select a subset of candidate states for which APMs are transported to the next stage of the trellis based on the neighborhood map. This eliminates the need to sort the remaining APMs during reduced state trellis equalization. The neighborhood map identifies a subset of the highest probability neighbors for an ML state. The subset of candidate states identified as highest probability neighbors may be saved in a look-up table. The look-up table may be generated offline and/or generated/updated dynamically during run-time operation.

A digital signal processing method and apparatus is described. The digital processing apparatus comprises a coarse carrier recovery module for performing a coarse carrier compensation of a received modulated signal; and a trellis-based equalization module selectable between a first mode for performing a trellis-based equalization to compensate a residual inter-symbol interference of the received modulated signal and a second mode for performing a trellis-based equalization to compensate a residual phase noise of the received modulated signal.

Embodiment reduced-state trellis equalization techniques compute accumulated path metrics (APMs) for a subset of candidate states for at least some stages in the trellis based on a neighborhood map of an ML state. This reduces the number of APMs that are computed and stored during trellis equalization. Other embodiments select a subset of candidate states for which APMs are transported to the next stage of the trellis based on the neighborhood map. This eliminates the need to sort the remaining APMs during reduced state trellis equalization. The neighborhood map identifies a subset of the highest probability neighbors for an ML state. The subset of candidate states identified as highest probability neighbors may be saved in a look-up table. The look-up table may be generated offline and/or generated/updated dynamically during run-time operation.

An apparatus and method for transmitting digital broadcast signal are provided. The apparatus includes a group formatter to format a data group including mobile service data, where the group formatter further maps the mobile service data into a data group of interleaved format, adds N training sequences into a corresponding location of the data group of interleaved format, adds signaling data into the data group of interleaved format, inserts place holder bytes for MPEG header and non-systematic Reed-Solomon (RS) parity into the data group of interleaved format, and deinterleaves the mobile service data in the data group of interleaved format, a non-systematic RS encoder to non-systematic RS encode the mobile service data in the formatted data group and insert non-systematic RS parity obtained from the non-systematic RS encoding into the formatted data group.

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 wireless communication system is described which includes a transmitter operable to transmit a transmitted signal, the transmitter having one or more transmitting antennae, a receiver operable to receive a received signal, the receiver having one or more receiving antennae, wherein lattice reduction is used in obtaining, at the receiver, an estimate of the transmitted signal based on the received signal, characterized in that the lattice reduction utilizes a lattice reduction matrix, a decomposed representation of which is transmitted between the transmitter and the receiver.

An apparatus and method for transmitting digital broadcast signal are provided. The apparatus includes a group formatter to format a data group including mobile service data, where the group formatter further maps the mobile service data into a data group of interleaved format, adds N training sequences into a corresponding location of the data group of interleaved format, adds signaling data into the data group of interleaved format, inserts place holder bytes for MPEG header and non-systematic Reed-Solomon (RS) parity into the data group of interleaved format, and deinterleaves the mobile service data in the data group of interleaved format, a non-systematic RS encoder to non-systematic RS encode the mobile service data in the formatted data group and insert non-systematic RS parity obtained from the non-systematic RS encoding into the formatted data group.

A method for operating a receiving device includes determining reliability ratings for undecoded data streams in a received transmission, selecting an undecoded data stream in the received transmission in accordance with the determined reliability ratings, thereby producing a selected data stream, and decoding the selected data stream with a decoding trellis, thereby producing a data symbol. The method also includes updating the decoding trellis in accordance with the data symbol, and repeating the selecting, the decoding, and the updating for remaining undecoded data streams in the received transmission.

In a spatial modulation multiple-input-multiple-output (SM-MIMO) wireless communication system, multiple transmitting antennae and multiple receiving antennae may be utilized to respectively transmit and receive wireless signals for the communication. A selection of a combination of the multiple transmitting antennae may be configured to represent one or more binary digits in a signal sequence. The signal sequence may be produced at the receiving end without the knowledge of the selection of the combination of the multiple transmitting antennae.

Systems (100) and methods for co-channel separation of communication signals. The methods involve: simultaneously receiving a plurality of communication signals transmitted at disparate relative Doppler frequencies from different locations within a multi-access system; performing matched filtering operations to pre-process each of the plurality of communication signals so as to generate pre-processed digitized samples using a priori information contained in pre-ambles (302, 304) of messages present within the plurality of communication signals; using estimated signal parameters to detect the plurality of communication signals from the pre-processed digitized samples; and demodulating the plurality of communication signals without using a Viterbi decoder.