Systems and methods for transmitting data using various Modulation on Zeros schemes are described. In many embodiments, a communication system is utilized that includes a transmitter having a modulator that modulates a plurality of information bits to encode the bits in the zeros of the z-transform of a discrete-time baseband signal. In addition, the communication system includes a receiver having a decoder configured to decode a plurality of bits of information from the samples of a received signal by: determining a plurality of zeros of a z-transform of a received discrete-time baseband signal based upon samples from a received continuous-time signal, identifying zeros that encode the plurality of information bits, and outputting a plurality of decoded information bits based upon the identified zeros.

A discrete Fourier transform spread orthogonal time frequency space modulation method comprises the steps of performing DFT preceding processing and delay-Doppler domain mapping processing on the transmit data symbols, OTFS modulator, and performing delay-Doppler domain demapping processing and IDFT decoding processing on a received signal to realize demodulation; compared with the existing waveforms, including OFDM and DFT-s-OFDM, the proposed DFT-s-OTFS can reduce the bit error rate under high Doppler spread and the peak-to-average power ratio of the transmitted signal at the same time.

Disclosed is a secure and adaptive waveforms multiplexing system in advanced-level wireless communication systems (such as 5G and beyond systems).

A pilot reception processing method includes: determining a first position of a pilot pattern corresponding to a pilot in a delay-Doppler domain; and determining first indication information according to the first position.

Apparatuses, methods, and systems are disclosed for precoding wireless communications. An apparatus includes a processor and a memory coupled with the processor. The memory includes instructions that are executable by the processor to cause the apparatus to precode a set of symbols over a set of resources using a transform precoder that constrains a search space of codewords to a unit hypersphere such that the transform precoder comprises a spherical codebook having an angular threshold distance between codewords and to combine the precoded symbols in a redundant manner such that multiple parts of precoded symbols are used to protect against loss of the set of symbols.

A communications system comprises a maximum ratio combining (MRC) circuit for receiving a plurality of input data streams and for processing the plurality of input data streams using maximum ration combining to improve signal to noise ratio. A MIMO transmitter transmits the MRC processed carrier signal over a plurality of separate communications links from the MIMO transmitter, each of the plurality of separate communications links from one transmitting antenna of a plurality of transmitting antennas to each of a plurality of receiving antennas at a MIMO receiver.

An access node, user equipment, apparatuses, methods, and computer programs for a communication system. An apparatus for a wireless transmitter device includes a transmitter module for transmitting wireless transmissions and a processing module, which controls the transmitter module. The processing module generates one or more transmit symbols in a Delay-Doppler domain to obtain a Delay-Doppler representation; transforms the Delay-Doppler representation into a Time-Frequency domain to obtain a Time-Frequency representation, the Time-Frequency representation having a first bandwidth and a first duration; adds pilot symbols to the Time-Frequency representation to obtain a Time-Frequency representation with an extended second bandwidth or an extended second duration; transforms the Time-Frequency representation with the extended second bandwidth or the extended second duration to the time domain to obtain a time domain representation; and transmits the time domain representation to a wireless receiver device.

Methods, systems and devices for lattice reduction in decision feedback equalizers for orthogonal time frequency space (OTFS) modulation are described. An exemplary wireless communication method, implementable by a wireless communication receiver apparatus, includes receiving a signal comprising information bits modulated using OTFS modulation scheme. Each delay-Doppler bin in the signal is modulated using a quadrature amplitude modulation (QAM) mapping. The method also includes estimating the information bits based on an inverse of a single error covariance matrix of the signal, with the single error covariance matrix being representative of an estimation error for all delay-Doppler bins in the signal.

A method for the OTFS coded transmission of data. To improve the bit error rate for transmission of OTFS-coded signals that are processed based on integer Doppler shifts, the guard interval is expanded over the complete Doppler dimension or, alternatively, the guard interval extends over the complete delay dimension of the OTFS-coded frame in situations of either large Doppler shifts or large delays, especially as the quadruple of the Doppler shifts approaches or exceeds the extension of the Doppler domain in the OTFS frame or twice the delay delays approach or exceeds the extension of the delay domain in the OTFS frame.

A method for adaptive transmitter symbol arrangement in delay-Doppler domain grids including retrieving one or more current communication relevant parameters; deriving from the one or more current communication relevant parameters at least a maximum expected Doppler frequency shift for a transmitted signal; placing at least one pilot symbol in a delay-Doppler domain grid; placing a minimum number of guard symbols around the at least one pilot symbol in the delay-Doppler domain grid so the guard symbols occupy a guard space around the at least one pilot so any grid position outside the guard space around the at least one pilot has a distance along the first grid direction exceeding the derived first guard space parameter and also has a distance along the second grid direction that exceeds the second guard space parameter; and placing data symbols in the delay-Doppler domain grid outside the guard space for data transmission.