A decoding apparatus (10) includes a multi-input branch metric calculation unit (11) configured to calculate, by using a branch label corresponding to a path extending toward a state S at a time point N in a trellis diagram and a plurality of reception signal sequences, a branch metric in the state S, a path metric calculation unit (12) configured to calculate a path metric in the state S at the time point N, and a surviving path list memory (13) configured to store path labels corresponding to L path metrics among a plurality of calculated path metrics. The path metric calculation unit (12) generates a path label in the state S at the time point N by combining the branch label with a path label in each of the states at the time point N−1 and the surviving path list memory (13) outputs path labels corresponding to L path metrics.

A gaussian frequency shift keying (GFSK) detector comprising a multi-symbol detector; at least three Viterbi decoders, and a timing adjustment module. The multi-symbol detector receives a series of samples representing a received GFSK modulated signal which comprises at least three samples per symbol; and generates, for each set of samples representing an N-symbol sequence of the GFSK modulated signal, at least three sets of soft decisions values, each set of soft decision values indicating the probability that the N-symbol sequence of samples is each possible N-symbol pattern based on a different one of the at least three samples of a symbol being a centre sample of the symbol. Each Viterbi decoder generates, for each N-symbol sequence, a path metric for each possible N-symbol pattern from a different set of soft decision values according to a Viterbi decoding algorithm. The timing adjustment module generates a timing adjustment signal based on the path metrics generated by the Viterbi decoders to adjust the sample timing.

Provided are a transmitter and a method for transmitting a data block in a wireless communication system. The method comprises the following steps: deciding the number of bits (s) and encoders (N.sub.ES) to allocate to one axis of a signal constellation; encoding an information bit based on the s and the N.sub.ES and generating a coded block; parsing the coded block based on the s and the N.sub.ES and generating a plurality of frequency sub-blocks; and transmitting the plurality of frequency sub-blocks to a receiver.

A method of generating a transmit signal by a transmitter for transmission to a receiver includes receiving input data, generating a base symbol signal, the base symbol signal, generating a perturbation signal based on the input data, and combining the base symbol signal and the perturbation signal to generate the transmit signal.

An optical module processes first FEC (Forward Error Correction) encoded data produced by a first FEC encoder. The optical module has a second FEC encoder for further coding a subset of the first FEC encoded data to produce second FEC encoded data. The optical module also has an optical modulator for modulating, based on a combination of the second FEC encoded data and a remaining portion of the first FEC encoded data that is not further coded, an optical signal for transmission over an optical channel. The second FEC encoder is an encoder for an FEC code that has a bit-level trellis representation with a number of states in any section of the bit-level trellis representation being less than or equal to 64 states. In this manner, the second FEC encoder has relatively low complexity (e.g. relatively low transistor count) that can reduce power consumption for the optical module.

A data processing apparatus, a data processing method, and a program are disclosed. They improve communication performance by performing bit interleaving suitable for a modulation method that is a non-uniform constellation. One example of a data processing apparatus includes a mapping unit configured to generate a second bit sequence by mapping a first bit sequence to any symbol on a complex plane corresponding to a NUC modulation method, an inter-symbol interleaving unit configured to generate a third bit sequence by performing inter-symbol interleaving to the second bit sequence, an intra-symbol interleaving unit configured to generate a fourth bit sequence by performing intra-symbol interleaving for shifting M bits as a whole of the third bit sequence per a same number of M bits as the bit number M representing the symbol, and a modulation unit configured to wirelessly transmit the fourth bit sequence according to the NUC modulation method.

A method for data retrieval includes receiving a set of probability metrics. A set of probability metrics is received for each one of a plurality of read values, and each probability metric of the set of probability metrics corresponds to a statistical likelihood that the read value is representative of one of a number of symbols. The symbols define a set of allowed transitions between a number of states, and a series of successive allowed transitions between states define allowed paths between the states. The method further includes determining a survival path between the states. The survival path is based on an accumulation of probability metrics corresponding to the statistical likelihood that successive ones of the plurality of read values are representative of successive ones of the symbols defining each transition in the survival path. The method further includes decoding a symbol stream based on the survival path.

A channel encoding method in a communication or broadcasting system is provided. The channel encoding method includes reading a first sequence corresponding to a parity check matrix, converting the first sequence to a second sequence by applying a certain rule to a block size corresponding to a parity check matrix and the first sequence, and encoding information bits based on the second sequence. The block size has at least two different integer values.

A channel encoding method in a communication or broadcasting system is provided. The channel encoding method includes reading a first sequence corresponding to a parity check matrix, converting the first sequence to a second sequence by applying a certain rule to a block size corresponding to a parity check matrix and the first sequence, and encoding information bits based on the second sequence. The block size has at least two different integer values.

An optical module processes first FEC (Forward Error Correction) encoded data produced by a first FEC encoder. The optical module has a second FEC encoder for further coding a subset of the first FEC encoded data to produce second FEC encoded data. The optical module also has an optical modulator for modulating, based on a combination of the second FEC encoded data and a remaining portion of the first FEC encoded data that is not further coded, an optical signal for transmission over an optical channel. The second FEC encoder is an encoder for an FEC code that has a bit-level trellis representation with a number of states in any section of the bit-level trellis representation being less than or equal to 64 states. In this manner, the second FEC encoder has relatively low complexity (e.g. relatively low transistor count) that can reduce power consumption for the optical module.