A transmitting apparatus and a receiving apparatus are provided. The transmitting apparatus includes: an encoder configured to generate a low density parity check (LDPC) codeword by performing LDPC encoding; an interleaver configured to interleave the LDPC codeword; and a modulator configured to modulate the interleaved LDPC codeword according to a modulation method to generate a modulation symbol. The interleaver includes a block interleaver formed of a plurality of columns each comprising a plurality of rows, and the block interleaver is configured to divide the plurality of columns into at least two parts and interleave the LDPC codeword.

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 for increasing the efficiency and robustness of non-orthogonal multiple access (NOMA) schemes may include storing relationships that associate codewords with values of bit sets, receiving information bits and converting the information bits into bit sets, determining codewords associated with the bit sets, and transmitting the determined codewords. A first codeword may be pre-defined for a WTRU. A second codeword associated with a first bit set may be determined using a first relationship between the first codeword and a value of the first bit set. A third codeword associated with a second bit set may be determined using a second relationship between the second codeword and a value of the second bit set.

A transmission method includes mapping processing, phase change processing, and transmission processing. In the mapping processing, a plurality of first modulation signals and a plurality of second modulation signals are generated using a first mapping scheme, and a plurality of third modulation signals and a plurality of fourth modulation signals are generated using a second mapping scheme. In the phase change processing, a phase change is performed on the plurality of second modulation signals and the plurality of fourth modulation signals using all N kinds of phases. In the transmission processing, the first modulation signals and the second modulation signals are respectively transmitted at a same frequency and a same time from different antennas, and the third modulation signals and the fourth modulation signals are respectively transmitted at a same frequency and a same time from the different antennas.

Quadrature amplitude modulation (QAM) techniques for use in optical systems are described. An optical transceiver may include a modulator configured to modulate data according to a scaled set-partitioning QAM (SP-QAM) scheme. The modulator may be configured to receive a plurality of bits, associate the plurality of bits with a plurality of symbols according to the scaled (SP-QAM) scheme; and transmit the plurality of symbols over an optical channel. A demodulator in an optical receiver may receive the plurality of symbols transmitted over the optical channel and associate the received symbols with a plurality of bits according to the scaled (SP-QAM) scheme; and provide the plurality of bits to a forward error correction decoder.

In various embodiments, a system comprising a network interface, a processor, and a non-transient memory medium operatively coupled to the processor is disclosed. The memory medium is configured to store a plurality of instructions configured to program the processor to receive a digital bit stream, transform the digital bit stream to an encoded digital bit stream. The encoded digital bit stream comprises at least one of a gateway channel, a composite channel, or a data channel and any combination thereof, and provides the encoded digital bit stream to the network interface for transmission. A non-transitory computer-readable memory medium and a computer-implemented method are disclosed.

Consistent with the present disclosure, codewords indicative of a super Gaussian distribution may be encoded and decoded using the encoders and decoders disclosed herein. Based on such codewords, symbols may be transmitted in accordance or in conformance with a super Gaussian distribution to tailor the SE of an optical signal or subcarrier for a given link having non-linear degradations and shaping gain. Such tailed SE may not be achievable with a Gaussian symbol transmission probability distribution.

Transmitting apparatus and receiving apparatus for communication systems using coded orthogonal frequency-division multiplexed (COFDM) dual-subcarrier modulation (DCM) signals. The same coded data is mapped both to COFDM subcarriers located in the lower-frequency half spectrum of the DCM signal and to COFDM subcarriers located in its upper-frequency half spectrum. The mapping of COFDM subcarriers in those half spectra employ labeling diversity preferred for reception of DCM with less error when accompanied by interfering additive white Gaussian noise (AWGN). In preferred forms of COFDM DCM signal, the quadrature amplitude modulation (QAM) of COFDM subcarriers is Gray mapped to position palindromic lattice-point labels along one of the diagonals of each square QAM constellation.

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 (NES) to allocate to one axis of a signal constellation; encoding an information bit based on the s and the NES and generating a coded block; parsing the coded block based on the s and the NES and generating a plurality of frequency sub-blocks; and transmitting the plurality of frequency sub-blocks to a receiver.

The present patent application relates to a transmission method and corresponding receiving methods. The transmission method comprises: selecting K number of data streams for transmission, wherein each data stream comprises one or more data messages; and independently for each data stream k=0, . . . , K1: encoding and modulating data messages of the kth data stream using a Trellis Coded Modulation, TCM, scheme TCM.sub.k, interleaving the encoded and modulated data messages of the k-th data stream by using a stream specific interleaver .sub.k, scrambling the interleaved data messages of the k-th data stream by using a stream specific scrambling sequence; combining all scrambled data messages of the K number of data streams into at least one transmission signal s(l); and transmitting the at least one transmission signal s(l) over a radio channel of the wireless communication system.