Systems and methods provide for a network test that by capturing in-phase values of a reflected signal off a transmission medium or irregularity therein. The in-phase values are converted to time-domain, which is then halved and converted back to the frequency domain to identify calculated quadrature values associated with the measured in-phase values. The measured in-phase values and calculated quadrature values may be used to determine impedance reflection/transmission characteristics of transmission medium or an irregularity therein. The measured in-phase values and calculated quadrature values may be used to determine if the transmission medium is minimum phase.

An apparatus for wireless communication includes a receiver configured to receive control information associated with a non-coherent transmission to a base station. The apparatus further includes a transmitter configured to perform the non-coherent transmission based on the control information. The non-coherent transmission includes transmission of a codepoint to the base station, and the codepoint is determined based a diagonalized base sequence parameter matrix, a first discrete Fourier transform (DFT) matrix of a first size, and a second DFT matrix of a second size.

Provided are a data sending method and apparatus, a data receiving method and apparatus, a data transmission system, and a storage medium. The data sending method includes: a first data stream is acquired, where the first data stream includes multiple coded data symbols; an N-dimensional orthogonal transformation is performed on the first data stream to obtain an orthogonally transformed first data stream, where N≥2; a modulation processing is performed on the orthogonally transformed first data stream to obtain a first radio frequency signal; and the first radio frequency signal is sent.

A signal processing apparatus (10) according to the present disclosure includes: an overlap-type FFT processing unit (11) that performs FFT processing overlapping input subcarrier signals each other for each of FFT blocks, and a generation unit (12) that generates a signal which is obtained by frequency shifting the subcarrier signals that have been subjected to the FFT processing by the overlap-type FFT processing unit (11) by a frequency shift amount of a subcarrier, a phase offset that occurs between the FFT blocks overlapping each other being compensated in the signal.

The disclosure relates to a communication technique and a system for converging a fifth generation (5G) and subsequent communication system with Internet of things (IoT) technology to support a higher data transmission rate than a fourth generation (4G) system. The disclosure is applied to the intelligent service based on the 5G and subsequent communication technology and IoT-related technology. The reception device according to the disclosure receives orthogonal frequency division multiplexing (OFDM) signals through a plurality of antennas, aligns the received OFDM signals, converts at least one of the aligned reception signals into a designated symbol, estimates the data symbols of the reception signals based on the designated condition, and determines the data symbol of the reception signals by synthesizing at least one of the converted reception signals among the estimated reception signals.

The present disclosure discloses a method and a system for transmitting DFT-s-OFDM symbols. A data sequence for transmitting as an OFDM symbol is received as input from a data source. A reference sequence for transmitting along with the data sequence as the OFDM symbol is generated and time-multiplexed with the data sequence, to generate a multiplexed sequence. Thereafter, a Discrete Fourier Transform (DFT) operation is performed on the multiplexed sequence to generate a DFT-spread-Orthogonal Frequency Division Multiplexing (DFT-s-OFDM) symbol that is further processed for transmitting over a channel. The transmission of the reference sequence and the data sequence in a single OFDM symbol provides better bandwidth utilization and flexibility in modulation of the reference sequence and the data sequence.

Methods, systems, and devices for wireless communications are described. A wireless device may generate a orthogonal time frequency space (OTFS) waveform for transmission to a second wireless device. Generation of an OTFS waveform may include mapping information samples to a delay-Doppler resource grid having a set of delay values and a set of Doppler values. A channel estimation block may occupy one or more rows of the delay-Doppler grid. When mapping information samples to the delay-Doppler grid, the transmitting device may first map information samples in the delay dimension (e.g., first map all of the symbols in one column of the delay-Doppler grid before mapping information samples into a second column). Such a mapping scheme may reduce the distance from any given information sample to the channel estimation block.

An apparatus and system to compensate for phase noise in a 5G or 6G DFT-S-OFDM signal are described. An access port (AP)-specific orthogonal cover code (OCC) is applied to phase tracking reference signal (PTRS) symbols in each of a plurality of PTRS groups. The PTRS group are inserted between data symbols to form a data vector prior to perform transform precoding, on the data vector and transmission to a UE. The UE extracts the PTRS symbols from different PTRS APs using the OCC specific to each AP. After extraction, the phase noise for each PTRS group is estimated and used to compensate the data symbols associated with the PTRS group.

When a frequency deviation compensation amount is compensated for by use of frequency shift, a phase offset occurs between adjacent input blocks included in a plurality of input blocks as divided, with the result that an error occurs in a reconstructed bit sequence. A frequency deviation compensation system of the invention is characterized by comprising: a frequency deviation compensation means for compensating for a frequency deviation occurring in a signal by use of frequency shift; and a phase offset compensation means for compensating for a phase offset occurring, in the signal, due to the frequency shift.

An apparatus for wireless communication includes a receiver configured to receive control information associated with a non-coherent transmission to a base station. The apparatus further includes a transmitter configured to perform the non-coherent transmission based on the control information. The non-coherent transmission includes transmission of a codepoint to the base station, and the codepoint is determined based a diagonalized base sequence parameter matrix, a first discrete Fourier transform (DFT) matrix of a first size, and a second DFT matrix of a second size.