An apparatus serves a plurality of user equipments in a wireless communication system. For transmitting/receiving data of a plurality of user equipments, which include at least a first user equipment and a second user equipment, on resources shared by the plurality of user equipments, the apparatus transmits/receives a first data signal of the first user equipment and second data signal of the second user equipment using a non-orthogonal multiple access, NOMA, scheme. The first data signal and the second data signal are modulated using different waveforms prior to superposition of the first and second data signals.

A method and an apparatus for transmitting broadcast signals thereof are disclosed. The apparatus for transmitting broadcast signals comprises an encoder for encoding service data, a mapper for mapping the encoded service data into a plurality of OFDM (Orthogonal Frequency Division Multiplex) symbols to build at least one signal frame, a frequency interleaver for frequency interleaving data in the at least one signal frame by using a different interleaving-seed which is used for every OFDM symbol pair comprised of two sequential OFDM symbols, a modulator for modulating the frequency interleaved data by an OFDM scheme and a transmitter for transmitting the broadcast signals having the modulated data, wherein the different interleaving-seed is generated based on a cyclic shifting value and wherein an interleaving seed is variable based on an FFT size of the modulating.

A method for wireless communication at a user equipment (UE) includes receiving, from a base station, a slot parameter that configures the UE to receive a number of symbols within a self-contained slot. The method also includes receiving, from the base station, a cyclic prefix (CP) parameter associated with a single symbol of the number of symbols, the CP parameter indicating a source of samples for a CP included at a beginning of the single symbol. The method further includes receiving, from the base station, the number of symbols within the self-contained slot. In some examples, a guard interval (GI) may be included at one or both of an end or a beginning of each symbol of the number of symbols. The CP may be outside a single FFT window of a number of FFT windows, associated with the single symbol of the number of symbols.

Systems and techniques are described that are directed to filter frequency response shift compensation, including compensating for shifting in the rejection band of the filter. Compensation for the shifting in the rejection band can include applying a pre-distortion to attenuate edge resource units (RUs), and applying PHY Protocol Data Unit (PPDU) scheduling schemes. For example, a PPDU scheduling scheme reduce bandwidth in the channel, thereby dropping the out of band RUs. Front ends provide feedback to a respective radio, which allows that radio to apply the appropriate pre-distortion. The front ends can include one or more filters enabling frequency domain coexistence between collocated radios operating in the differing Wi-Fi bands, and a coupler that provides the feedback indicating the frequency response shift to a radio. The radio can then apply a digital pre-distortion to compensate for the shifting in the rejection band.

In one embodiment, an apparatus includes: a radio frequency (RF) front end circuit to receive and downconvert a RF signal to a second frequency signal, the RF signal comprising an orthogonal frequency division multiplexing (OFDM) transmission; a digitizer coupled to the RF front end circuit to digitize the second frequency signal to a digital signal; and a baseband processor coupled to the digitizer to process the digital signal. The baseband circuit comprises a first circuit having a first plurality of correlators having an irregular comb structure, each of the first plurality of correlators associated with a carrier frequency offset and to calculate a first correlation on a first portion of a preamble of the OFDM transmission.

Provided are a data modulation method and apparatus, and a storage medium. The method includes: modulating a data sequence [b(i)] to obtain a data sequence [s(k)]; wherein [s(k)] has the following characteristics: in a case where $k=2i,s\left(k\right)=\frac{e^{j\left(\frac{\pi }{2}\left(i\mathrm{mod}2\right)+\theta \right)}}{\sqrt{2}}[\left(1-2b\left(i\right)\right)+j(1-2b$

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may receive, from a transmitter, a reference signal block provided based at least in part on an orthogonal frequency division multiplexing (OFDM) waveform. The UE may perform an estimation operation based at least in part on the reference signal block. The UE may receive a data transmission via a single carrier waveform based at least in part on the estimation operation. Numerous other aspects are provided.

Methods, systems, and devices for wireless communications are described. Pre-discrete Fourier transform (DFT) time-domain spreading codes may be applied for UE multiplexing for uplink control information (e.g., over shared resources of an uplink slot). For example, a moderate number of UEs may be multiplexed within the same slot by having each UE spread modulation symbols before DFT-spreading by different spreading code. For orthogonality across UEs, the pre-DFT spreading codes may be selected as orthogonal cover codes (OCCs). The spreading sequences can be generated from a set of any orthogonal sequences or generated from unitary matrices. In some cases, orthogonality in the time domain may be kept as well as a frequency division multiplexed (FDM) structure in the frequency domain. For such property, a Fourier basis OCC design may be used. In some other examples, a Hadamard matrix based OCC design may be used.

A method for implementing a fast UBDM transform includes receiving a first, input vector via a processor, and partitioning the first vector to produce a magnitude vector and a sign vector. A second vector, including a modified magnitude vector and a modified sign vector, is generated by: applying a permutation to the magnitude vector to produce the modified magnitude vector, converting the sign vector, based on an algorithm, into an intermediate sign vector, and applying nonlinear layers to the intermediate sign vector. Each nonlinear layer includes a permutation, an S-box transformation, a diffusive linear operation and/or an Xor operation. Multiple linear layers are applied to the second vector to produce a third vector, the third vector being a transformed version of the first vector. A first signal representing the third vector is sent to at least one transmitter for transmission of a second signal representing the transformed data vector.

A transmission method simultaneously transmitting a first modulated signal and a second modulated signal at a common frequency performs precoding on both signals using a fixed precoding matrix and regularly changes the phase of at least one of the signals, thereby improving received data signal quality for a reception device.