A coding and modulation apparatus and method are presented. The apparatus comprises an encoder that encodes input data into cell words, and a modulator that modulates said cell words into constellation values of a non-uniform constellation. The modulator is configured to use, based on the total number M of constellation points of the constellation and the code rate, a non-uniform constellation from one or several groups of constellations each comprising one or more constellations.

A communication device includes an acquisition unit that acquires a bit sequence, and a conversion unit that converts the bit sequence to a predetermined complex constellation point sequence including a plurality of complex constellation points including a non-zero complex constellation point and a zero complex constellation point. At least one of the predetermined complex constellation point sequences is a first complex constellation point sequence in which each of a plurality of complex constellation points constituting the complex constellation point sequence is converted to any complex constellation point or zero complex constellation point of a first signal constellation including non-power of two number of complex constellation points. The conversion unit converts one of the bit sequences to at least the first complex constellation point sequence.

Embodiments include devices and methods that improves quality in radio transmission/reception using a single-carrier scheme and/or a multi-carrier scheme.

The invention provides a method for nonlinear compensation of coherent high-capacity high-order QAM system, including: deploying an OPC on an intermediate link of communication between a transmitter and receiver, and performing phase conjugation on a transmitted signal based on the OPC to generate idler; performing phase recovery on a compensated signal at the receiver to obtain a constellation diagram, simulating a nonlinear function relationship between a transmitted signal and a received signal by using a trained and learned CVDNN, and performing nonlinear compensation on the constellation diagram to obtain the compensated constellation diagram; and calculating a Q-factor based on the compensated constellation diagram, and evaluating communication performance by the Q-factor. Nonlinear compensation is performed on a transmitted signal by using an OPC+CVDNN method to equalize nonlinear degradation of an optical fiber in a WDM coherent optical communication system.

To provide improved phase noise tolerance and improved identification of certain fault types, a modulation/demodulation procedure is disclosed for 5G and 6G. The transmitter can modulate a message according to the amplitude and phase of the overall waveform to be emitted, modulated according to predetermined amplitude and phase levels of the modulation scheme. The receiver can then separate the received waveform into orthogonal I and Q branches and measure their branch amplitudes, as usual. The receiver can then convert the branch amplitude measurements back into the original amplitude-phase modulation parameters using formulas provided. The receiver can then demodulate the message by comparing the overall amplitude and phase of each message element to the predetermined amplitude and phase levels of the modulation scheme, which thereby provides substantially increased phase noise tolerance at high frequencies. The procedure can also diagnose fault types and identify faulted message elements specifically, among other benefits.

A subchannel encoding device is configured to include: a probability distribution shaping-encoding unit for dividing M×N (M is an integer of two or more, and N is an integer of one or more) subchannels into N groups, shaping a probability distribution of transmission modulation symbols of each group on the basis of signal-to-noise ratios of the M×N subchannels, and converting an information bit string into a shaped bit string corresponding to the probability distribution of the transmission modulation symbols of each group; a subchannel signal generating unit for generating each subchannel signal in the M×N subchannels from the shaped bit string; and a signal multiplexing unit for multiplexing the M×N subchannel signals generated by the subchannel signal generating unit to generate a subchannel multiplexed signal.

Aspects are provided which allow for a base station to transmit code blocks according to a frequency first per layer (FFPL) mapping, and for a UE to decode received code blocks according to the FFPL mapping. The base station maps a plurality of code blocks to multiple layers, where each of the code blocks is mapped to a plurality of resource elements initially by frequency and subsequently by time on only a single layer of the multiple layers. The base station then transmits data including the code blocks to a UE. Afterwards, the UE receives the data including the mapped code blocks in multiple layers from the base station, and the UE decodes the code blocks based on the mapping. Thus, improvements in link efficiency, reliability, and reduced power consumption compared to frequency first (FF) mapping approaches may be achieved.

A coding and modulation apparatus and method are presented. The apparatus comprises an encoder that encodes input data into cell words, and a modulator that modulates said cell words into constellation values of a non-uniform constellation. The modulator is configured to use, based on the total number M of constellation points of the constellation and the code rate, a non-uniform constellation from one or several groups of constellations each comprising one or more constellations.

The guard-space reference disclosed herein is a signal transmitted in the guard spaces separating message data intervals, and configured to reveal amplitude noise or phase noise or both, using 5G or 6G technology. For example, the transmitter can transmit an I-branch with a predetermined amplitude level, and an orthogonal Q branch with zero amplitude, in the guard space. The receiver can measure the received amplitude and phase of the guard-space reference, subtract the initial amplitude and phase, and thereby measure both phase noise and amplitude noise. The receiver can then subtract the measured amplitude and phase effects from the message data, thereby negating both phase noise and amplitude noise. Guard-space references disclosed herein can preserve the inter-subcarrier orthogonality, inter-symbol separation, and signal circularity advantages of prior art, while additionally providing both amplitude noise and phase noise mitigation. Examples are suitable for wireless standards.

An efficient baseband predistortion linearization method for reducing the spectral regrowth and compensating memory effects in wideband communication systems using effective multiplexing modulation technique such as wideband code division multiple access and orthogonal frequency division multiplexing is disclosed. The present invention is based on the method of piecewise pre-equalized lookup table based predistortion, which is a cascade of a lookup table predistortion and piecewise pre-equalizers.