Qualcomm Incorporated

Raviteja Patchava

Xiaoxia Zhang

Morteza Soltani

Jun Ma

Jing X Sun

Tao Luo

Iyab Issam Sakhnini

Zhifei Fan

Peter S Gaal

Hemant Saggar

Junyi Li

Piyush Gupta

Ahmed Abdelaziz Ibrahim Abdelaziz Zewail

Juan Montojo

Sony Akkarakaran

Dung Ngoc Doan

Elyes Balti

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may receive a configuration that indicates, within each symbol of a plurality of symbols, an extra guard interval (GI) before data and a tail GI after the data. The UE may decode first data within a first symbol of the plurality of symbols at a first time location that is based at least in part on the extra GI and the tail GI within the first symbol. The UE may decode second data within a second symbol of the plurality of symbols at a second time location that is based at least in part on the tail GI within the second symbol. Numerous other aspects are described.

Extra guard interval

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.

Techniques for rate matching order for orthogonal time frequency space multiplexing

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a first network entity may receive, from a second network entity, an indication of a first frequency offset associated with the second network entity. In some aspects, the first network entity may receive, from the second network entity, a first transmission including a first communication and a first helper signal that are separated in a frequency domain based on the first frequency offset. In some aspects, the first network entity may decode, via envelope tracking, the first transmission to obtain the first communication from the first transmission. Numerous other aspects are provided.

Helper signal based envelope tracking

Methods, systems, and devices for wireless communications are described. A user equipment (UE) may receive first control signaling identifying a demodulation reference signal (DMRS) pattern that may be uniformly distributed in a time domain and a frequency domain. The DMRS pattern may include a first set of resource elements for the DMRS, a second set of resource elements for guard tones adjacent to and greater in frequency than the first set of resource elements, and a third set of resource elements for guard tones adjacent to and lower in frequency than the first set of resource elements. The UE may receive second control signaling that schedules a data signal to be communicated between the UE and a network node in a set of time-frequency resources. The UE may communicate the data signal according to the second control signaling and the DMRS according to the DMRS pattern.

Modified demodulation reference signal patterns for orthogonal frequency-division multiplexing

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may precode a physical sidelink control channel (PSCCH) communication using a first delay-Doppler precoder. The UE may precode a physical sidelink shared channel (PSSCH) communication using one or more second delay-Doppler precoders. The UE may transmit the PSCCH communication and the PSSCH communication in a slot after precoding the PSCCH communication and the PSSCH communication. Numerous other aspects are described.

Orthogonal time frequency space precoding of control channel and shared channel communications

This disclosure provides systems, methods and apparatus, including computer programs encoded on computer storage media, for demodulation reference signal (DMRS) precoding in high-Doppler scenarios. In some aspects, communicating devices may support different precodings for different portions of a signal, such as for a DMRS portion and an information portion. For example, a device may receive a signal including an orthogonal time-frequency space (OTFS) precoded first waveform portion carrying DMRS symbols and an orthogonal frequency division multiplexing (OFDM) precoded second waveform portion carrying information symbols. The device may transform the OTFS precoded DMRS symbols from a time-frequency domain to a delay-Doppler domain, may use the DMRS symbols to estimate a delay-Doppler channel, and may use the delay-Doppler channel estimate to measure an inter-carrier interference (ICI). The receiving device may use the ICI measurement to receive the information symbols carried by the OFDM precoded second waveform portion.

Demodulation reference signal precoding in high-doppler scenarios

Methods, systems, and devices for wireless communications are described. For example, a wireless device may support physical broadcast channel (PBCH) precoding in high-doppler scenarios. In some cases, a base station may generate a synchronization signal block (SSB) including synchronization signals and PBCH signaling. The base station may transmit, to a UE, the PBCH signaling in accordance with an orthogonal time frequency space (OTFS) precoding and the synchronization signals in accordance with a non-OTFS precoding. The UE may monitor for the SSB and receive the PBCH signaling in accordance with the OTFS precoding and the synchronization signals in accordance with a non-OTFS precoding. The UE may establish or modify a connection with the base station according to the PBCH signaling.

Physical broadcast channel precoding in high-doppler scenarios

Methods, systems, and devices for wireless communications are described. A network node may transmit a set of reference signals via a corresponding set of antennas, each antenna in the corresponding set of antennas associated with a unique precoding vector, wherein each precoding vector uses a combinational codeword based on a combination of codewords from a set of available codewords. The network node may receive, from an energy harvesting (EH)-capable device, a set of frequency-shifted backscatter responses corresponding to at least a subset of the set of reference signals. The network node may transmit, to the EH-capable device, a signal based on channel state information, wherein the channel state information is based on the set of frequency-shifted backscatter responses.

Two stage codebook beamforming for channel estimation in passive devices

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a network entity may obtain a singular value decomposition (SVD) precoding vector that is based at least in part on backscatter associated with a reference signal transmitted by the network entity. The network entity may apply the SVD precoding vector to an output signal. The network entity may transmit the output signal based at least in part on a set of antennas. Numerous other aspects are described.

Precoding vector based on singular value decomposition characterization of a communication channel

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a first network node may apply an orthogonal time frequency space (OTFS) precoding to a plurality of tracking reference signal (TRS) resource samples allocated in a delay-Doppler domain to obtain a plurality of TRS symbols with the OTFS precoding. The first network node may transmit, to a second network node, a TRS in which the plurality of TRS symbols with the OTFS precoding have a uniform spacing in a time domain. Numerous other aspects are described.

Orthogonal time frequency space precoding for tracking reference signal

Certain aspects of the present disclosure provide techniques for hybrid modulation and demodulation, which may include multiplexing and demultiplexing different waveform types. An example method includes receiving a time-domain waveform from a transmitting entity and converting the time-domain waveform to a frequency domain. The method also includes identifying a first set of time and frequency resources associated with converted first information and a second set of time and frequency resources associated with second information in time and frequency resources of an orthogonal frequency domain multiplexing (OFDM) resource grid in a time-frequency domain. The method further includes decoding the first set of time and frequency resources to generate first information from the converted first information. For certain aspects, the first information may be precoded with an orthogonal time frequency space (OTFS) modulation.

Hybrid orthogonal frequency division multiplexing

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.

Shifting a fast Fourier transform (FFT) window to generate a self-contained slot

Certain aspects of the present disclosure provide techniques for using a guard interval in a delay-Doppler domain. A method of wireless communication includes converting information in a delay-Doppler domain to a time-frequency domain, wherein the information includes data and at least one guard interval (GI); mapping the converted information to time and frequency resources of an orthogonal frequency domain multiplexing (OFDM) resource grid in the time-frequency domain; generating a time-domain waveform based on the OFDM resource grid, wherein the time-domain waveform includes one or more GIs; and outputting the time-domain waveform for transmission to a node.

Guard interval in delay-Doppler domain

Aspects present herein relate to methods and devices for wireless communication including an apparatus, e.g., a UE and/or a base station. The apparatus may encode a plurality of bits associated with QAM, the plurality of bits corresponding to a circular buffer associated with at least one RV, the plurality of bits including a plurality of systematic bits. The apparatus may also transfer the plurality of bits from the circular buffer associated with the at least one RV to a first buffer and a second buffer. Additionally, the apparatus may map the plurality of bits from the first buffer and the second buffer to a plurality of modulation symbols.

Rate matching and channel interleaving for probabilistic shaping

Disclosed are techniques for wireless communication. In an aspect, a wireless device maps data, a unique word (UW) sequence, and a suppression signal to a set of reserved time-domain resources based on a time-domain resource mapping and reservation rule to produce DFT input data. DFT processing is performed on the DFT input data to produce IFFT input data. IFFT processing is performed on the IFFT input data to produce the GI-based waveform with a data part (e.g., non-zero part) and a tail part (e.g., zero tail part). The wireless device may further transmit the GI-based waveform.

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San Diego, CA, United States of America

Raviteja Patchava