Aspects described herein relate to adding a set of redundant subcarriers to a set of data subcarriers to be transmitted in a unique-word orthogonal frequency division multiplexing (UW-OFDM) waveform, interleaving, based on a permutation matrix, the set of redundant subcarriers with the set of data subcarriers to generate a permutation of subcarriers, mapping the permutation of subcarriers as input to an inverse fast Fourier transform (IFFT), and generating the UW-OFDM waveform based on output of the IFFT. Other aspects relate to receiving and processing the UW-OFDM waveform.

An Orthogonal Frequency Division Multiplexing (OFDM) transmitter generates OFDM multiple-access signals with low Peak-to-Average-Power Ratio (PAPR). A code-division multiplexer arranges original data symbols from different data streams inside each length-N symbol block, which is spread by a Discrete Fourier Transform (DFT) spreader. The arrangement of the original data symbols configures the DFT spreader to spread each original data symbol into a predetermined spread-DFT code division multiple access channel. The resulting DFT-spread data symbols are mapped to OFDM subcarriers, and an inverse discrete Fourier transform (IDFT) operates on the DFT-spread data symbols to generate an OFDM transmission signal having low PAPR.

There is provided a method of transmitting and receiving data across a network. A receiver device comprises a recovery module comprising a neural network trained to recover signals from clipped signals. The transmitter device may clip the original signal more aggressively due to the improved performance of the machine-learning based recovery module, thereby reducing the Peak to Average Power Ratio (PAPR) of the signal.

Methods, systems, and devices for wireless communications are described in which control information is transmitted using a single carrier (SC) waveform in time domain blocks without a cyclic prefix (CP). A base station may configure a user equipment (UE) for control information transmissions using a SC waveform without CPs in time domain blocks, and may activate the SC waveform without CPs in time domain blocks based on one or more parameters. The control information may be non-uniformly segmented across two or more time domain blocks or two or more portions of a time domain block. A reference signal, such as a demodulation reference signal, may be transmitted in the time domain blocks, where the reference signals may be distributed evenly or unevenly across the time domain blocks.

Embodiments of the present disclosure relate to systems and methods to generate a signal in a communication network. The method comprises filtering a discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-s-OFDM) data signal, and one of a DFT-S-OFDM and orthogonal frequency division multiplexing (OFDM) reference signal (RS) using a data filter and a RS filter respectively, to produce filtered data signal and filtered RS. The RS filter has one to one relationship with the data filter. Thereafter, port mapping the filtered RS to a corresponding port assigned to the transmitter to obtain port mapped filtered RS, wherein the port mapped filtered RS comprises a first subset of non-zero locations comprising of the filtered RS values and a second subset of zero locations comprising of zero values.

The present invention is designed so that, when a CP-OFDM waveform is supported in the UL in addition to DFT-spreading OFDM waveform, transmission of UCI can still be controlled adequately. According to the present invention, a user terminal has a transmission section that transmits uplink control information (UCI), and a control section that controls transmission of the UCI based on a waveform of an uplink (UL) data channel or based on indication information provided via higher layer signaling and/or downlink control information (DCI).

The present disclosure provides techniques for bandwidth constrained communication systems with frequency domain information processing. A bandwidth constrained equalized transport (BCET) communication system can include a transmitter, a communication channel, and a receiver. The transmitter can include a pulse-shaping filter that intentionally introduces memory into a signal in the form of inter-symbol interference, an error control code (ECC) encoder, a multidimensional fast Fourier transform (FFT) processing block that processes the signal in the frequency domain, and a first interleaver. The receiver can include an information-retrieving equalizer, a deinterleaver with an ECC decoder, and a second interleaver joined in an iterative ECC decoding loop. The communication system can be bandwidth constrained, and the signal can comprise an information rate that is higher than that of a communication system without intentional introduction of the memory at the transmitter.

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a base station may receive, using a first beam, a first physical random access channel (PRACH) communication during a first random access channel (RACH) occasion. The base station may receive, during the first RACH occasion, a data communication having a timing that is aligned with a timing of the PRACH communication to provide a beam switching gap before reception of a second PRACH communication during a second RACH occasion. Numerous other aspects are described.

An over-the-air computation (AirComp) scheme is proposed for federated edge learning (FEEL) without channel state information (CSI) at the edge devices (EDs) or edge server (ES). The proposed scheme adopts the majority vote (MV) principle and uses pulse-position modulation (PPM) symbols constructed with discrete Fourier transform (DFT)-spread orthogonal frequency division multiplexing (OFDM) (DFT-s-OFDM) as votes from EDs. By taking the delay spread and synchronization errors into account, we show how to eliminate the need for truncated-channel inversion (TCI) at the EDs and detect MV at the ED with a non-coherent detector. The proposed method naturally reduces the peak-to-mean envelope power ratio (PMEPR) of the signal as it inherits the properties of the single-carrier (SC) waveform. An alternative proposed scheme also adopts the majority vote (MV) principle but further defines multiple subcarriers and orthogonal frequency division multiplexing (OFDM) symbols for voting options, which reduces to frequency-shift keying (FSK) over OFDM subcarriers as a special case. Since the votes from EDs are separated on orthogonal resources, the proposed scheme eliminates the need for truncated-channel inversion (TCI) at the EDs and allows the ES to detect MV with a non-coherent detector. We also mitigate the peak-to-mean envelope power ratio (PMEPR) of the synthesized signals by using randomization symbols. Through simulations, we show that the proposed schemes provide high test accuracy in fading channels for both independent and identically distributed (IID) and non-IID data while resulting in lower PMEPR symbols as compared to one-bit broadband digital aggregation (OBDA) with quadrature amplitude modulation (QAM).

This invention is directed to a terminal apparatus capable of preventing the degradation of reception quality of control information even in a case of employing SU-MIMO transmission system. A terminal, which uses a plurality of different layers to transmit two code words in which control information is placed, comprises: a resource amount determining unit that determines, based on a lower one of the encoding rates of the two code words or based on the average value of the reciprocals of the encoding rates of the two code words, resource amounts of control information in the respective ones of the plurality of layers; and a transport signal forming unit that places, in the two code words, the control information modulated by use of the resource amounts, thereby forming a transport signal.