An example method may include obtaining multiple symbols each associated with a different state in a quadrature amplitude modulation scheme used for transmission of a data signal. The method may further include determining a sequence of symbols of the multiple symbols for a first portion of the data signal. The determining may include selecting an index value from multiple index values for the first portion of the data signal. The determining may also include obtaining energy states of multiple sequences of the symbols using the energy levels of the symbols. The determining may further include obtaining a relationship between the energy levels of the symbols, the energy states of the multiple sequences of the symbols, and the multiple index values. The determining may further include selecting the sequence of symbols based on the relationship and the index value for the first portion of the data signal.

A method for generating a non-uniform constellation is provided. The method comprises the step of performing a first process, the first process comprising the steps of: obtaining a first constellation defined by one or more parameter values; and generating a second constellation based on the first constellation using a second process. The second process comprises the steps of: obtaining a set of candidate constellations, wherein the set of candidate constellations comprises the first constellation and one or more modified constellations, wherein each modified constellation is obtained by modifying the parameter values defining the first constellation; determining the performance of each candidate constellation according to a predetermined performance measure; selecting the candidate constellation having the best performance as the second constellation.

A method of extremely high coding rates for next-generation wireless local area network (WLAN) systems involves coding an input data at a first coding rate using codes designed for coding up to a second coding rate lower than the first coding rate to provide a coded data. The method also involves wirelessly transmitting the coded data.

Techniques of defining a transmission scheme for NB-IoT data include determining the TBS based on 16-quadrature amplitude modulation (QAM) analysis but use quadrature phase-shift keying (QPSK) for modulation. For example, a base station (eNB) may determine that a UE is configured to receive or transmit data with 16-QAM modulation via capability signalling from the UE. Upon performing this determination, the eNB transmits configuration data to the UE, e.g., via DCI, configuring the UE to receive data over a narrowband physical downlink shared channel (NPDSCH) using 16-QAM modulation. Part of the configuration data indicates whether the UE is to support 16-QAM modulation with or without repetition via radio resource control (RRC) parameter modulation-restriction-Repetitions. Depending upon this indication, the UE may use quadrature phase-shift keying (QPSK) rather than 16-QAM despite selecting or being assigned a TBS based on 16-QAM modulation.

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.

In addition to the normal modulation states of 5G and 6G (BPSK, QPSK, 16QAM, etc.), the modulation scheme may include one or more zero-power states in which an amplitude is transmitted with very low or zero power. The receiver can detect the zero-power state and treat that state as an additional modulation state of the modulation scheme, thereby increasing the information content of each message element due to the additional number of modulation states available for encoding. Alternatively, the zero-power state or states may be used for special options, such as indicating a beginning or an ending of the message. Zero-power states may also be used to separate the message from an associated demodulation reference or to separate sequential messages. Substantial power may be saved since the zero-power states require very little (or no) transmitter power.

This disclosure describes systems, methods, and devices related to byte boundary shift. A device may utilize a probabilistic constellation shaping mechanism comprising a shaping encoder, a channel encoder, and a modulator to generate one or more QAM symbols. The device may set a shaping output block to have a fixed length of output bits. The device may set shaping input bits used in the shaping encoder, wherein the input bits are a multiple of a first number of bits.

A method of communication includes duplication of a first field of a first content channel into a third field in a third content channel and applying a modulation and coding scheme (MCS) to only one of the first field and the third field. The first content channel is a first portion of a frame and the third content channel is a third portion of the frame. Duplication of a second field of a second content channel into a fourth field in a fourth content channel and applying a modulation and coding scheme (MCS) to only one of the second field and the fourth field. The second content channel is a second portion of a frame and the fourth content channel is a fourth portion of the frame. The first content channel and the second content channel form a first group of content channels and the third content channel and the fourth content channel form a second group of content channels. The method then transmits the frame.

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 modulation method, including: modulating data by using a non-uniform constellation; and sending the modulated data. When the non-uniform constellation provided in embodiments of this application is used, for each noise standard deviation, a BER of the non-uniform constellation provided in embodiments of this application is lower than a BER of an existing QAM constellation.