FREQUENCY DOMAIN MULTIPLEXING OF A DATA SIGNAL AND A REFERENCE SIGNAL

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a transmitting device may generate a frequency-domain-multiplexed signal by performing frequency domain multiplexing of a data signal and a reference signal within a symbol of a discrete Fourier transform spread orthogonal frequency domain multiplexing waveform communication, the reference signal being one of a demodulation reference signal, a sounding reference signal, or a channel state information reference signal. The transmitting device may transmit, to a receiving device, the frequency-domain-multiplexed signal. Numerous other aspects are described.

FIELD OF THE DISCLOSURE

Aspects of the present disclosure generally relate to wireless communication and to techniques and apparatuses for frequency domain multiplexing of a data signal and a reference signal.

BACKGROUND

SUMMARY

Some aspects described herein relate to a method of wireless communication performed by a transmitting device. The method may include generating a frequency-domain-multiplexed signal by performing frequency domain multiplexing of a data signal and a reference signal within a symbol of a discrete Fourier transform spread orthogonal frequency domain multiplexing (DFT-s-OFDM) waveform communication, the reference signal being one of a demodulation reference signal, a sounding reference signal, or a channel state information reference signal. The method may include transmitting, to a receiving device, the frequency-domain-multiplexed signal.

Some aspects described herein relate to a method of wireless communication performed by a receiving device. The method may include receiving, from a transmitting device, a frequency-domain-multiplexed signal, the frequency-domain-multiplexed signal being associated with frequency domain multiplexing of a data signal and a reference signal within a symbol of a DFT-s-OFDM waveform communication, the reference signal being one of a demodulation reference signal, a sounding reference signal, or a channel state information reference signal. The method may include demapping the data signal and the reference signal from the frequency-domain-multiplexed signal.

Some aspects described herein relate to a transmitting device for wireless communication. The transmitting device may include one or more memories and one or more processors coupled to the one or more memories. The one or more processors may be configured to generate a frequency-domain-multiplexed signal by performing frequency domain multiplexing of a data signal and a reference signal within a symbol of a DFT-s-OFDM waveform communication, the reference signal being one of a demodulation reference signal, a sounding reference signal, or a channel state information reference signal. The one or more processors may be configured to transmit, to a receiving device, the frequency-domain-multiplexed signal.

Some aspects described herein relate to a receiving device for wireless communication. The receiving device may include one or more memories and one or more processors coupled to the one or more memories. The one or more processors may be configured to receive, from a transmitting device, a frequency-domain-multiplexed signal, the frequency-domain-multiplexed signal being associated with frequency domain multiplexing of a data signal and a reference signal within a symbol of a DFT-s-OFDM waveform communication, the reference signal being one of a demodulation reference signal, a sounding reference signal, or a channel state information reference signal. The one or more processors may be configured to perform a demapping of the data signal and the reference signal from the frequency-domain-multiplexed signal.

Some aspects described herein relate to a non-transitory computer-readable medium that stores a set of instructions for wireless communication by a transmitting device. The set of instructions, when executed by one or more processors of the transmitting device, may cause the transmitting device to generate a frequency-domain-multiplexed signal by performing frequency domain multiplexing of a data signal and a reference signal within a symbol of a DFT-s-OFDM waveform communication, the reference signal being one of a demodulation reference signal, a sounding reference signal, or a channel state information reference signal. The set of instructions, when executed by one or more processors of the transmitting device, may cause the transmitting device to transmit, to a receiving device, the frequency-domain-multiplexed signal.

Some aspects described herein relate to a non-transitory computer-readable medium that stores a set of instructions for wireless communication by a receiving device. The set of instructions, when executed by one or more processors of the receiving device, may cause the receiving device to receive, from a transmitting device, a frequency-domain-multiplexed signal, the frequency-domain-multiplexed signal being associated with frequency domain multiplexing of a data signal and a reference signal within a symbol of a DFT-s-OFDM waveform communication, the reference signal being one of a demodulation reference signal, a sounding reference signal, or a channel state information reference signal. The set of instructions, when executed by one or more processors of the receiving device, may cause the receiving device to perform a demapping of the data signal and the reference signal from the frequency-domain-multiplexed signal.

Some aspects described herein relate to an apparatus for wireless communication. The apparatus may include means for generating a frequency-domain-multiplexed signal by performing frequency domain multiplexing of a data signal and a reference signal within a symbol of a DFT-s-OFDM waveform communication, the reference signal being one of a demodulation reference signal, a sounding reference signal, or a channel state information reference signal. The apparatus may include means for transmitting, to a receiving device, the frequency-domain-multiplexed signal.

Some aspects described herein relate to an apparatus for wireless communication. The apparatus may include means for receiving, from a transmitting device, a frequency-domain-multiplexed signal, the frequency-domain-multiplexed signal being associated with frequency domain multiplexing of a data signal and a reference signal within a symbol of a DFT-s-OFDM waveform communication, the reference signal being one of a demodulation reference signal, a sounding reference signal, or a channel state information reference signal. The apparatus may include means for performing a demapping of the data signal and the reference signal from the frequency-domain-multiplexed signal.

DETAILED DESCRIPTION

Wireless communications exchanged between transmitting devices and receiving devices may be communicated using various waveforms. As wireless communications continue to utilize new frequency bands, viable types of waveforms may need to be selected in order for transmitting devices and receiving devices to effectively communicate with one another. For example, for certain high frequency bands, such as frequency range 4 (FR4) and higher bands, orthogonal frequency domain multiplexing (OFDM) based waveforms may be desirable in order to maintain backwards compatibility with lower frequency bands (e.g., frequency range 1 (FR1), frequency range 2 (FR2), frequency range 2x (FR2x), and similar bands) and/or in order to provide high spectral efficiency in scenarios where an energy efficiency requirement may be relaxed. Additionally, or alternatively, a single carrier waveform may be desirable for scenarios requiring high energy efficiency. For single carrier waveforms, a lower peak-to-average-power ratio (PAPR) may result in a higher power amplifier (PA) efficiency and/or extended battery life of a transmitting device and/or a receiving device. Moreover, single carrier waveforms may achieve a high data rate due to spectrum availability. In such examples, to facilitate frequency domain equalization, a cyclic prefix (CP) and/or a guard interval (GI) (sometimes referred to as a unique word (UW)) may be used to create OFDM-like blocks or symbols. In examples in which multiple waveforms may be used for a certain frequency range (e.g., FR4 or higher bands), slot-level and/or symbol-level alignment between OFDM waveforms and single carrier waveforms may be implemented, and/or a common numerology may be used between OFDM waveforms and single carrier waveforms, such as for a purpose of achieving a uniform transceiver design (e.g., a transceiver including uniform sampling rates and/or fast Fourier transform (FFT) sizes).

A location and/or a configuration of various reference signals exchanged between a transmitting device and a receiving device may differ according to a specific waveform being used for communication. For example, a CP-based OFDM waveform, sometimes referred to as a CP-OFDM waveform, may permit multiplexing of a reference signal (e.g., a demodulation reference signal (DMRS)) with downlink channels (e.g., a physical downlink shared channel (PDSCH), a physical downlink control channel (PDCCH), or a similar channel) in the frequency domain, within a same symbol. In such examples, a DMRS Type 1 configuration and/or a DMRS Type 2 configuration may define different DMRS resource element (RE) densities for a symbol. In such examples, using a cyclic prefix in connection with frequency domain multiplexing of a reference signal and other channels (e.g., PDSCH, PDCCH, or a similar channel) may ensure orthogonality between the reference signal and the other channels. Moreover, channel estimation may be conducted by a device based on the DMRS REs and by frequency-domain interpolation to cover all REs associated with the channel.

For a single carrier waveform with a CP or GI, multiplexing of a reference signal (e.g., DMRS) with other channels in the same symbol (e.g., in the time or frequency domain) may be more difficult, because multiplexing may lead to inter-symbol interference (ISI), such as between a DMRS and a PDSCH. Accordingly, in some examples, in order to avoid interference between a reference signal (e.g., a DMRS) and other channels in the same symbol, multiplexing of a reference signal and another channel may be limited to inter-symbol level. In such examples, a DMRS or similar reference signal may be front-loaded over a half slot or a full slot, such that the DMRS or similar reference signal occupies one or more symbols at the beginning of the half slot or full slot. This may result in high reference signal overhead and otherwise inefficient usage of network resources. For example, for tracking fast time varying channels, such as channels associated with high frequency bands and/or millimeter wave (mmWave) communications, multiple reference signals may need to be received, such as for a purpose of effective channel tracking in high Doppler scenarios. In such examples, allocating multiple symbols to a reference signal (e.g., a DMRS or a similar reference signal) may result in large overhead, reduced throughput, high latency, and overall inefficient usage of network resources.

Some aspects described herein enable frequency domain multiplexing of a data signal and a reference signal using a discrete Fourier transform spread orthogonal frequency domain multiplexing (DFT-s-OFDM) waveform, thus reducing reference signal overhead. In some aspects, a transmitting device (e.g., a user equipment (UE), a network node, or another wireless communication device) may generate a frequency-domain-multiplexed (FDMed) signal, such as by performing frequency domain multiplexing of a data signal (e.g., a PDSCH signal, a physical uplink shared channel (PUSCH) signal, or a similar data signal) and a reference signal (e.g., a DMRS, a sounding reference signal (SRS), a channel state information (CSI) reference signal (CSI-RS), or another reference signal) within a symbol of a DFT-s-OFDM waveform communication, and the transmitting device may transmit the FDMed signal to a receiving device (e.g., a UE, a network node, or another wireless communication device). The receiving device may perform a demapping of the FDMed signal in order to extract the reference signal and the data signal from the FDMed signal. In some aspects, the transmitting device may optimize a density of the reference signal within the FDMed signal, such as for a purpose of striking a balance between overall waveform PAPR and estimation performance at the receiving device, and/or the transmitting device may select a reference signal sequence that strikes a balance between end-to-end performance and reference signal overhead. In this way, aspects described herein may enable robust channel estimation while reducing reference signal overhead as compared to other waveforms requiring full symbol allocations for reference signals, resulting in increased throughput, reduced latency, and overall more efficient usage of network resources.

In some aspects, the transmitting device described elsewhere herein may correspond to a network node110and/or a UE120. The transmitting device may include a communication manager140(e.g., when the transmitting device corresponds to a UE120) or a communication manager150(e.g., when the transmitting device corresponds to a network node110). As described in more detail elsewhere herein, the communication manager140and/or the communication manager150may generate a frequency-domain-multiplexed signal by performing frequency domain multiplexing of a data signal and a reference signal within a symbol of a DFT-s-OFDM waveform communication, the reference signal being one of a demodulation reference signal, a sounding reference signal, or a channel state information reference signal; and transmit, to a receiving device, the frequency-domain-multiplexed signal. Additionally, or alternatively, the communication manager140and/or the communication manager150may perform one or more other operations described herein.

In some aspects, the receiving device described elsewhere herein may correspond to a network node110and/or a UE120. The receiving device may include a communication manager140(e.g., when the receiving device corresponds to a UE120) or a communication manager150(e.g., when the receiving device corresponds to a network node110). As described in more detail elsewhere herein, the communication manager140and/or the communication manager150may receive, from a transmitting device, a frequency-domain-multiplexed signal, the frequency-domain-multiplexed signal being associated with frequency domain multiplexing of a data signal and a reference signal within a symbol of a DFT-s-OFDM waveform communication, the reference signal being one of a demodulation reference signal, a sounding reference signal, or a channel state information reference signal; and perform a demapping of the data signal and the reference signal from the frequency-domain-multiplexed signal. Additionally, or alternatively, the communication manager140and/or the communication manager150may perform one or more other operations described herein.

In some aspects, the transmitting device described elsewhere herein may correspond to the network node110or the UE120and/or may include means for generating a frequency-domain-multiplexed signal by performing frequency domain multiplexing of a data signal and a reference signal within a symbol of a DFT-s-OFDM waveform communication, the reference signal being one of a demodulation reference signal, a sounding reference signal, or a channel state information reference signal; and/or means for transmitting, to a receiving device, the frequency-domain-multiplexed signal. In some aspects, the means for the transmitting device to perform operations described herein may include, for example, one or more of communication manager150, transmit processor220, TX MIMO processor230, modem232, antenna234, MIMO detector236, receive processor238, controller/processor240, memory242, scheduler246, communication manager140, antenna252, modem254, MIMO detector256, receive processor258, transmit processor264, TX MIMO processor266, controller/processor280, or memory282.

In some aspects, the receiving device described elsewhere herein may correspond to the network node110or the UE120and/or may include means for receiving, from a transmitting device, a frequency-domain-multiplexed signal, the frequency-domain-multiplexed signal being associated with frequency domain multiplexing of a data signal and a reference signal within a symbol of a DFT-s-OFDM waveform communication, the reference signal being one of a demodulation reference signal, a sounding reference signal, or a channel state information reference signal; and/or means for demapping the data signal and the reference signal from the frequency-domain-multiplexed signal. In some aspects, the means for the receiving device to perform operations described herein may include, for example, one or more of communication manager150, transmit processor220, TX MIMO processor230, modem232, antenna234, MIMO detector236, receive processor238, controller/processor240, memory242, scheduler246, communication manager140, antenna252, modem254, MIMO detector256, receive processor258, transmit processor264, TX MIMO processor266, controller/processor280, or memory282.

FIG.4is a diagram illustrating an example400of physical channels and reference signals in a wireless network, in accordance with the present disclosure. As shown inFIG.4, downlink channels and downlink reference signals may carry information from a network node110to a UE120, and uplink channels and uplink reference signals may carry information from a UE120to a network node110.

As shown, a downlink channel may include a PDCCH that carries downlink control information (DCI), a PDSCH that carries downlink data, or a physical broadcast channel (PBCH) that carries system information, among other examples. In some aspects, PDSCH communications may be scheduled by PDCCH communications. As further shown, an uplink channel may include a physical uplink control channel (PUCCH) that carries uplink control information (UCI), a PUSCH that carries uplink data, or a PRACH used for initial network access, among other examples. In some aspects, the UE120may transmit acknowledgement (ACK) or negative acknowledgement (NACK) feedback (e.g., ACK/NACK feedback or ACK/NACK information) in UCI on the PUCCH and/or the PUSCH.

As further shown, a downlink reference signal may include a synchronization signal block (SSB), a CSI-RS, a DMRS, a positioning reference signal (PRS), or a phase tracking reference signal (PTRS), among other examples. As also shown, an uplink reference signal may include an SRS, a DMRS, or a PTRS, among other examples.

An SSB may carry information used for initial network acquisition and synchronization, such as a PSS, an SSS, a PBCH, and a PBCH DMRS. An SSB is sometimes referred to as a synchronization signal/PBCH (SS/PBCH) block. In some aspects, the network node110may transmit multiple SSBs on multiple corresponding beams, and the SSBs may be used for beam selection.

A CSI-RS may carry information used for downlink channel estimation (e.g., downlink CSI acquisition), which may be used for scheduling, link adaptation, or beam management, among other examples. The network node110may configure a set of CSI-RSs for the UE120, and the UE120may measure the configured set of CSI-RSs. Based at least in part on the measurements, the UE120may perform channel estimation and may report channel estimation parameters to the network node110(e.g., in a CSI report), such as a CQI, a precoding matrix indicator (PMI), a CSI-RS resource indicator (CRI), a layer indicator (LI), a rank indicator (RI), or an RSRP, among other examples. The network node110may use the CSI report to select transmission parameters for downlink communications to the UE120, such as a number of transmission layers (e.g., a rank), a precoding matrix (e.g., a precoder), an MCS, or a refined downlink beam (e.g., using a beam refinement procedure or a beam management procedure), among other examples.

A DMRS may carry information used to estimate a radio channel for demodulation of an associated physical channel (e.g., PDCCH, PDSCH, PBCH, PUCCH, or PUSCH). The design and mapping of a DMRS may be specific to a physical channel for which the DMRS is used for estimation. DMRSs are UE-specific, can be beamformed, can be confined in a scheduled resource (e.g., rather than transmitted on a wideband), and can be transmitted only when necessary. As shown, DMRSs are used for both downlink communications and uplink communications.

A PTRS may carry information used to compensate for oscillator phase noise. Typically, the phase noise increases as the oscillator carrier frequency increases. Thus, PTRS can be utilized at high carrier frequencies, such as millimeter wave frequencies, to mitigate phase noise. The PTRS may be used to track the phase of the local oscillator and to enable suppression of phase noise and common phase error (CPE). As shown, PTRSs are used for both downlink communications (e.g., on the PDSCH) and uplink communications (e.g., on the PUSCH).

A PRS may carry information used to enable timing or ranging measurements of the UE120based on signals transmitted by the network node110to improve observed time difference of arrival (OTDOA) positioning performance. For example, a PRS may be a pseudo-random Quadrature Phase Shift Keying (QPSK) sequence mapped in diagonal patterns with shifts in frequency and time to avoid collision with cell-specific reference signals and control channels (e.g., a PDCCH). In general, a PRS may be designed to improve detectability by the UE120, which may need to detect downlink signals from multiple neighboring network nodes in order to perform OTDOA-based positioning. Accordingly, the UE120may receive a PRS from multiple cells (e.g., a reference cell and one or more neighbor cells), and may report a reference signal time difference (RSTD) based on OTDOA measurements associated with the PRSs received from the multiple cells. In some aspects, the network node110may then calculate a position of the UE120based on the RSTD measurements reported by the UE120.

An SRS may carry information used for uplink channel estimation, which may be used for scheduling, link adaptation, precoder selection, or beam management, among other examples. The network node110may configure one or more SRS resource sets for the UE120, and the UE120may transmit SRSs on the configured SRS resource sets. An SRS resource set may have a configured usage, such as uplink CSI acquisition, downlink CSI acquisition for reciprocity-based operations, uplink beam management, among other examples. The network node110may measure the SRSs, may perform channel estimation based at least in part on the measurements, and may use the SRS measurements to configure communications with the UE120.

For certain waveforms, transmitting one or more of the reference signals shown inFIG.4may result in high overhead and/or inefficient usage of network resources. For example, for a single carrier waveform with a CP or GI, multiplexing of a reference signal (e.g., DMRS) with other channels in the same symbol (e.g., in the time or frequency domain) may be difficult, because multiplexing may lead to ISI, such as between a DMRS and a PDSCH. Accordingly, in some examples, in order to avoid interference between a reference signal (e.g., a DMRS) and other channels in the same symbol for certain waveforms, multiplexing of a reference signal and another channel may be limited to inter-symbol level. In such examples, a DMRS or similar reference signal may be front-loaded over a half slot or a full slot, such that the DMRS or similar reference signal occupies one or more symbols at the beginning of the half slot or full slot. This may result in high reference signal overhead and otherwise inefficient usage of network resources. For example, for tracking fast time varying channels, such as channels associated with high frequency bands and/or mm Wave communications, multiple reference signals may need to be transmitted throughout a slot, such as for a purpose of effective channel tracking in high Doppler scenarios. In such examples, allocating multiple symbols to a reference signal (e.g., a DMRS or a similar reference signal) may result in large overhead, reduced throughput, high latency, and overall inefficient usage of network resources.

Some techniques and apparatuses described herein enable frequency domain multiplexing of a data signal and a reference signal using a DFT-s-OFDM waveform, thus reducing reference signal overhead in higher band communications or otherwise. In some aspects, a transmitting device (e.g., a UE, a network node, or another wireless communication device) may generate a frequency-domain-multiplexed signal, such as by performing frequency domain multiplexing of a data signal (e.g., a PDSCH signal, a PUSCH signal, or a similar data signal) and a reference signal (e.g., a DMRS, an SRS, a CSI-RS, or another reference signal) within a symbol of a DFT-s-OFDM waveform communication, and the transmitting device may transmit the frequency-domain-multiplexed signal to a receiving device (e.g., a UE, a network node, or another wireless communication device). The receiving device may receive the frequency-domain-multiplexed signal via the DFT-s-OFDM waveform communication and/or may perform a demapping of the data signal and the reference signal from the frequency-domain-multiplexed signal. The transmitting device may optimize a density of the reference signal within the frequency-domain-multiplexed signal, such as for a purpose of striking a balance between overall waveform PAPR and estimation performance at the receiving device, and/or may select a reference signal sequence to strike a balance between end-to-end performance and reference signal overhead. In this way, aspects may enable robust channel estimation while reducing reference signal overhead as compared to other waveforms requiring full symbol allocations for reference signals, resulting in increased throughput, reduced latency, and overall more efficient usage of network resources.

FIGS.5A-5Care diagrams illustrating an example500associated with transmitter and receiver chains for frequency domain multiplexing of a data signal and a reference signal, in accordance with the present disclosure. The example500may include communications between a transmitting device (e.g., a network node110, a UE120, or another wireless communication device) and a receiving device (e.g., a network node110, a UE120, or another wireless communication device). In some aspects, the transmitting device and the receiving device may be included in a wireless network, such as wireless network100. The transmitting device and the receiving device may communicate via a wireless access link (e.g., when one of the transmitting device and the receiving device is a network node110and the other one of the transmitting device and the receiving device is a UE120), which may include an uplink and a downlink, and/or via a sidelink (e.g., when the transmitting device and the receiving device are both UEs).

In some aspects, a data signal (e.g., a PDSCH signal, a PUSCH signal, or a similar signal) and a reference signal (shown as “RS” inFIGS.5A-5C, which may be a DMRS, an SRS, a CSI-RS, or a similar reference signal) may be FDMed within a symbol of a DFT-s-OFDM waveform communication, such as for a purpose of reducing overhead associated with certain reference signals and/or enabling tracking of a fast time varying channel, among other purposes. In such aspects, a transmitting device may directly multiplex a reference signal with a DFT-precoded data signal in the frequency domain, or else may multiplex a DFT-precoded reference signal with a DFT-precoded data signal in the frequency domain. For example,FIG.5Ashows an example of a transmitter chain associated with direct frequency domain multiplexing of a reference signal with a DFT-precoded data signal in the frequency domain.

As indicated by reference number502, the reference signal may be received at the transmitter chain and may be fed to a serial-to-parallel (S/P) converter504, resulting in a number of samples (sometimes referred to as tones) associated with the reference signal, referred to herein as “Np” and indicated inFIG.5Aby reference number506. Moreover, as indicated by reference number508, the data signal may be received at the transmitter chain, and similarly may be fed to an S/P converter510, resulting in a number of samples associated with the data signal, referred to herein as “Nd” and indicated inFIG.5Aby reference number512. In this example, the data signal may be DFT-precoded by the reference signal may not be DFT-precoded. Accordingly, the data signal samples, Nd, may be fed to a DFT precoder514having a size corresponding to Nd, resulting in NdDFT-precoded data signal samples, indicated by reference number516.

The Npreference signal samples and the NdDFT-precoded data signal samples may be fed to a frequency mapping component518for performing a frequency domain multiplexing of the reference signal samples and the data signal samples, resulting in an FDMed signal. In some aspects, Npmay be less than or equal to Nd, such that performing the frequency domain mapping between the reference signal samples and the data signal samples results in one or more data signal samples separating subsequent reference signal samples, in the frequency domain. Put another way, in the FDMed signal, every Ni+1 RE, in the frequency domain, may carry a reference signal sample, with the remaining REs carrying data signal samples. For example, in the aspect shown inFIG.5A, and as indicated by reference number519. Niis equal to 2, such that every third RE, in the frequency domain, carries a reference signal sample, with the remaining REs carrying a data signal samples. Thus, for M total REs allocated to a user, every Ni+1 RE may correspond to a reference signal sample (with a total quantity of reference signal samples equal to Np), and with the remaining quantity of REs (e.g., M minus Np) corresponding to data signal samples (e.g., M−Np=Nd).

In that regard, as indicated by reference number520, the signal leaving the frequency mapping component518may include M REs, including NpREs carrying reference signal samples interleaved with Nddata signal samples. The signal (e.g., the M REs) may then be fed to a subcarrier mapping component522, resulting in N subcarrier mapped REs, as indicated by reference number524. The N subcarrier mapped REs may be fed to an iFFT component526(e.g., an N-point iFFT component) in order to convert the signal from the frequency domain to the time domain, thus resulting in N time domain samples, as indicated by reference number528. The N time domain samples may then be fed to a parallel-to-serial component530, resulting in serialized N time domain samples, as indicated by reference number532. And the serialized signal may be fed to a cyclic prefix component534in order to add a cyclic prefix to the signal, as indicated by reference number536. The signal with cyclic prefix appended thereto may then be wirelessly transmitted to a receiving device, which is described in more detail below in connection withFIG.5C.

FIG.5Bshows an alternative example of a transmitter chain in which a DFT-precoded reference signal is FDMed with a DFT-precoded data signal. In this example, the Npsamples leaving the S/P converter504, described above in connection with reference number506, may be fed to a DFT precoder538having a size corresponding to Np, resulting in NpDFT-precoded data signal samples, indicated by reference number540. The NpDFT-precoded reference signal samples and the NdDFT-precoded data signal samples may be fed to the frequency mapping component518for performing a frequency domain multiplexing of the reference signal samples and the data signal samples, resulting in an FDMed signal, as described above in connection withFIG.5A. The remaining operations of the transmitter chain shown inFIG.5Bmay be performed in a substantially similar manner as described above in connection with the transmitter chain shown inFIG.5A. In some aspects, performing DFT precoding for both the reference signal samples and the data signal samples may result in certain PAPR advantages, which are described in more detail below.

FIG.5Cshows an example of a receiver chain associated with demapping an FDMed signal associated with a DFT-s-OFDM waveform communication, such as an FDMed signal generated using one of the transmitter chains described above in connection withFIGS.5A and5C. As indicated by reference number541, a receiving device may receive the signal generated by a transmitting device, such as the CP-based signal described above in connection with reference number536. The signal may be fed to a CP component542, which in this instance may strip the CP from the signal, resulting in a signal associated with N subcarrier mapped samples, as indicated by reference number544. The signal may be fed to an FFT component546(e.g., an N-point FFT component) in order to convert the signal from the time domain to the frequency domain, resulting in N frequency domain samples, as indicated by reference number548. The N frequency domain samples may be fed to a subcarrier demapping component550, which may be capable of demapping the N frequency domain samples from the corresponding subcarriers, resulting in the M samples, as indicated by reference number552(e.g., the Ndplus Npsamples described above in connection with the frequency mapping component518). The M samples may be fed to an equalizer component554in order to undergo an equalization process (e.g., a process used to reduce or eliminate ISI prior to symbol detection), resulting in M equalized samples, indicated by reference number556.

The M equalized samples may be fed to a frequency demapping component558, which perform demapping of the reference signal samples (e.g., Np, as indicated by reference number560) and the data signal samples (e.g., Nd, as indicated by reference number562). Put another way, the receiving device may be capable of demapping the interleaved reference signal samples from the surrounding data signal samples, thereby resulting in two coherent signals (e.g., a reference signal, as indicated by reference number564, and a data signal, described below in connection with reference number570). The receiving device may then perform channel estimation or a similar procedure using the reference signal. Moreover, the receiving device may perform additional processing on the data signal samples (e.g., Na), such as by feeding the data signal samples to a DFT component566(e.g., a DFT component having a size corresponding to Na), resulting in NdDFT-processed samples, indicated by reference number568, from which the receiving device may retrieve the data signal, as indicated by reference number570.

In some aspects, frequency domain multiplexing a reference signal with a data signal in this manner may result in reduced reference signal overhead while permitting tracking of fast time-varying channels and other communication benefits with little or no adverse effect on a PAPR of a data signal. For example, in some aspects, for a data signal associated with QPSK that is FDMed with a Zadoff-Chu (ZC) sequence (root 1) DMRS, a 50% DMRS density (e.g., Ni=1) may exhibit an almost identical PAPR performance as compared to a data-only signal at a 10−3complementary cumulative distribution function (CCDF) point, a 33% DMRS density (e.g., Ni=2) may exhibit an approximately 1 decibel (dB) loss in PAPR as compared to a data-only signal at a 10−3CCDF point, a 25% DMRS density (e.g., Ni=3) may exhibit an approximately 1.2 dB loss in PAPR as compared to a data-only signal at a 10−3CCDF point, and a 15% DMRS density may exhibit an approximately 1.55 dB loss in PAPR as compared to a data-only signal at a 10−3CCDF point. In some other aspects, for a data signal associated with 16 quadrature amplitude modulation (QAM) that is FDMed with a ZC sequence (root 1) DMRS, a 50% DMRS density (e.g., Ni=1) may exhibit a better PAPR performance (e.g., an approximately 0.4 dB gain in PAPR) as compared to a data-only signal at a 10−3CCDF point, a 33% DMRS density (e.g., Ni=2) may exhibit an approximately 0.5 dB loss in PAPR as compared to a data-only signal at a 10−3CCDF point, a 25% DMRS density (e.g., Ni=3) may exhibit an approximately 0.6 dB loss in PAPR as compared to a data-only signal at a 10−3CCDF point, and a 15% DMRS density may exhibit an approximately 1.03 dB loss in PAPR as compared to a data-only signal at a 10−3CCDF point.

In some other aspects, for a data signal associated with 256 QAM that is FDMed with a ZC sequence (root 1) DMRS, a 50% DMRS density (e.g., Ni=1) may exhibit a better PAPR performance (e.g., an approximately 0.52 dB gain in PAPR) as compared to a data-only signal at a 10−3CCDF point, a 33% DMRS density (e.g., Ni=2) may exhibit an approximately 0.37 dB loss in PAPR as compared to a data-only signal at a 10−3CCDF point, a 25% DMRS density (e.g., Ni=3) may exhibit an approximately 0.45 dB loss in PAPR as compared to a data-only signal at a 10−3CCDF point, and a 15% DMRS density may exhibit an approximately 1.1 dB loss in PAPR as compared to a data-only signal at a 10−3CCDF point. In some other aspects, for a data signal associated with 16 QAM that is FDMed with a w/2 binary phase-shift keying (BPSK) DMRS (e.g., π/2 BPSK with frequency-domain spectral shaping (FDSS)), a 50% DMRS density (e.g., Ni=1) may exhibit a better PAPR performance (e.g., an approximately 0.35 dB gain in PAPR) as compared to a data-only signal at a 10−3CCDF point, a 33% DMRS density (e.g., Ni=2) may exhibit an approximately 0.6 dB loss in PAPR as compared to a data-only signal at a 10−3CCDF point, and a 25% DMRS density (e.g., Ni=3) may exhibit an approximately 0.85 dB loss in PAPR as compared to a data-only signal at a 10−3CCDF point.

In that regard, with Ni=1 (e.g., a 50% reference signal density) and QPSK modulation, the PAPR of a data signal may be only slightly better than a PAPR of an FDMed data signal and a ZC sequence DMRS. Moreover, for Ni=1 and 64 QAM modulation, a PAPR of a data-only signal may actually be worse than a PAPR of an FDMed data signal and a ZC sequence DMRS. This may be because, is some aspects,

Accordingly, for a reference signal density of 50% (e.g., Ni=1), and considering that an average power of a data signal and a DMRS may be the same, a total average power may be doubled, but a peak power may not necessarily be doubled, particularly for high order modulations such as 64 QAM and 256 QAM. This may be because a ZC sequence DMRS has a low PAPR, and thus, when added to a high PAPR waveform, the ZC sequence DMRS may not heavily affect the peak values but may change the average power for high densities.

Accordingly, a trade-off may exist in terms of PAPR performance between the density of low PAPR waveform for DMRS and high PAPR for a data signal. Additionally, or alternatively, when frequency domain multiplexing a reference signal with a data signal, a density of a reference signal, in the frequency domain, and/or a type of reference signal sequence used may impact overall PAPR. Accordingly, in some aspects, a transmitting device may select a reference signal density, sequence, or other characteristics in an effort to optimize a reduction in reference signal overhead while maintaining an integrity of an estimated channel and/or overall PAPR performance. Aspects of transmitting device selecting one or more reference signal attributes and/or frequency domain multiplexing a reference signal with a data signal are described in more detail below in connection withFIG.6.

As indicated above,FIGS.5A-5Care provided as an example. Other examples may differ from what is described with respect toFIGS.5A-5C.

FIG.6is a diagram of an example600associated with frequency domain multiplexing of a data signal and a reference signal, in accordance with the present disclosure. As shown inFIG.6, a transmitting device605(e.g., a network node110, such as a CU, a DU, and/or an RU; a UE120; or another wireless communication device) may communicate with a receiving device610(e.g., a network node110, such as a CU, a DU, and/or an RU; a UE120; or another wireless communication device). In some aspects, the transmitting device605and the receiving device610may be part of a wireless network (e.g., wireless network100). The transmitting device605and the receiving device610may have established a wireless connection prior to operations shown inFIG.6. In some aspects, the transmitting device605and the receiving device610may communicate via a high frequency band, such as FR4 or a higher band.

As indicated by reference number615, the receiving device610may transmit, and the transmitting device605may receive, capability information (e.g., a capabilities report). In some aspects, the capability information may indicate a capability of the receiving device610to process an FDMed signal that is associated with a DFT-s-OFDM waveform (e.g., a signal that includes a reference signal and a data signal FDMed in a symbol of an DFT-s-OFDM communication). For example, in some aspects, the receiving device610may correspond to a UE120, and the transmitting device605may correspond to a network node110. In such aspects, the UE120may indicate, to the network node110(e.g., via a capabilities report) the UE120's capability to process an FDMed reference signal and data signal.

As indicated by reference number620, based at least in part on the receiving device610having a capability to process an FDMed reference signal and data signal, the transmitting device may select certain parameters for an FDMed communication (e.g., a DFT-s-OFDM waveform communication that is used to transmit an FDMed reference signal and data signal). For example, in some aspects, the transmitting device605may select a density of the reference signal within the FDMed signal, such as by selecting an Niparameter for the FDMed signal. Additionally, or alternatively, the transmitting device605may select an optimal reference signal density in order to strike a balance between an overall waveform PAPR and a channel estimation performance at the receiving device610, such as when a DMRS is being FDMed with a data signal.

Additionally, or alternatively, the transmitting device605may select a reference signal sequence associated with the FDMed signal. For example, in some aspects, the transmitting device605may select a reference signal sequence that strikes a balance between end-to-end performance and reference signal overhead. More particularly, in some aspects a π/2 BPSK with FDSS sequence may result in channel estimation performance loss at low signal to noise ratio (SNR) points because, with FDSS, a spectrum associated with a reference signal is no longer flat. Accordingly, the transmitting device605may determine whether to use π/2 BPSK, with or without FDSS, or whether to use a different reference signal sequence, for a given FDMed signal. In some aspects, the transmitting device605may select one of the reference signal sequences described above in connection withFIGS.5A-5C, such as a ZC sequence, a π/2 BPSK without FDSS, a π/2 BPSK with FDSS, or a similar reference signal sequence.

In some aspects, the transmitting device605may select a density of a reference signal within the FDMed signal and/or a reference signal sequence based at least in part on an MCS associated with the FDMed signal (e.g., an MCS used for the data signal transmission, such as one of QPSK, 16 QAM, 256 QAM, or the like). For example, as described above in connection withFIGS.5A-5C, higher a modulation order may result in lower loss in PAPR for low density reference signals in an FDMed signal. Accordingly, a selected reference signal density may be higher for low modulation orders (e.g., a selected Nimay be relatively small for low modulation orders, such as 1 or 2, resulting in densities of 50% or 33%, respectively), and a selected reference signal density may be lower for high modulation orders (e.g., a selected Nimay be relatively large for high modulation orders, such as 3 or more, resulting in densities of 25% or smaller).

In some aspects, the transmitting device605may select a reference signal sequence to be used and/or a density of the reference signal within the FDMed signal based at least in part on a number of transmission layers (e.g., a transmission rank of the communication). For example, in higher-rank MIMO communications, a precoder may be used by the transmitting device605, and thus a selection of a reference signal sequence and/or the density of the reference signal in the frequency domain may be dependent on transmission rank. More particularly, for line of sight (LoS) MIMO channels, a precoder used for the MIMO transmission may be diagonal, and thus the transmitting device may select a reference signal sequence and/or a density of the reference signal based on similar considerations as for rank one transmissions. However, for non-LoS MIMO channels, a selection of a reference signal sequence and/or a density of the reference signal may be dependent on the specific precoder matrix used for the MIMO transmission.

As shown by reference number625, the transmitting device605may transmit, and the receiving device610may receive, configuration information or similar information that includes one or more indications about a FDMed signal to be transmitted via a DFT-s-OFDM waveform. In some aspects, the receiving device610may receive the configuration information or similar information via one or more of RRC signaling, one or more MAC control elements (MAC-CEs), DCI, and/or UCI, among other examples. In some aspects, the configuration information or similar information may include an indication of one or more configuration parameters (e.g., already known to the receiving device610and/or previously indicated by the transmitting device605or other network device) for selection by the receiving device610, and/or explicit configuration information for the receiving device610to use to configure the receiving device610, among other examples.

In some aspects, the configuration information or similar information may indicate a density of the reference signal within the FDMed signal (e.g., as selected via the operations described above in connection with reference number620). For example, the configuration information or similar information may explicitly indicate the reference signal density or else may indicate a parameter indicative of the reference signal density, such as the Niparameter described above in connection withFIGS.5A-5C. Additionally, or alternatively, the configuration information or similar information may indicate a frequency mapping between the data signal and the reference signal in the FDMed signal. Such information may be helpful for demapping the reference signal and/or the data signal from the FDMed signal, which is described in more detail below in connection with reference number640. Additionally, or alternatively, the configuration information or similar information may indicate a selected reference signal sequence associated with the FDMed signal. For example, the configuration information may indicate that the reference signal will be associated with one of a ZC sequence, a π/2 BPSK sequence with or without FDSS, or another reference signal sequence.

As shown by reference number630, based at least in part on one or more selected parameters (such as the one or more parameters described above in connection with reference numbers620and625), the transmitting device605may generate an FDMed signal by performing frequency domain multiplexing of a data signal and a reference signal within a symbol of a DFT-s-OFDM waveform communication. In some aspects, the reference signal may be one of a DMRS, an SRS, a CSI-RS, or a similar reference signal. Additionally, or alternatively, the data signal may be associated with one of a PDSCH, a PUSCH, or a similar channel. In some aspects, the DFT-s-OFDM waveform communication may be associated with a high SNR operating point, such as a communication associated with a high modulation order. For high SNR operating points, a channel estimation SNR may be relatively high, and thus reducing overhead of a reference signal (e.g., DMRS) in the frequency domain for a DFT-s-OFDM waveform communication may not adversely affect end-to-end performance. Additionally, or alternatively, the DFT-s-OFDM waveform communication may be associated with fast time-varying channels, and thus frequency domain multiplexing the data signal and the reference signal (e.g., DMRS) may result in a good tradeoff between reference signal overhead and error performance.

As described above in connection withFIGS.5A and5B, in some aspects a reference signal to be frequency domain multiplexed with a data signal may be DFT-precoded, while, in some other aspects, a reference signal to be frequency domain multiplexed with a data signal may not be DFT-precoded (e.g., a non-DFT-precoded reference signal may be directly multiplexed with a DFT-precoded data signal). Put another way, in some aspects, the data signal in the FDMed signal is DFT-precoded and the reference signal in the FDMed signal is not DFT-precoded, while, in some other aspects, the data signal and the reference signal in the FDMed signal are DFT-precoded.

Additionally, or alternatively, in aspects in which the receiving device610transmitted capability information (e.g., a capabilities report) to the transmitting device605, the operations shown and described in connection with reference number630(e.g., the transmitting device605generating the FDMed signal) may be based at least in part on the capability information. Moreover, the operations shown and described in connection with reference number630May include performing one or more of the other operations described above in connection withFIGS.5A and5B, such as, in addition to DFT precoding one or both of the reference signal and the data signal, performing frequency mapping between the data signal and the reference signal, performing subcarrier mapping, performing an iFFT operation, or performing additional transmitter chain operations. As indicated by reference number635, the transmitting device605may transmit, and the receiving device610may receive, the FDMed signal (e.g., a DFT-s-OFDM waveform communication including the FDMed signal).

As indicated by reference number640, upon receiving the FDMed signal (e.g., upon receiving a DFT-s-OFDM waveform communication including the FDMed signal), the receiving device610may perform a demapping of the data signal and the reference signal from the FDMed signal. For example, the receiving device may perform one or more of the operations described above in connection with the demapping component inFIG.5C. Moreover, the operations shown and described in connection with reference number640may include performing one or more of the other operations described above in connection with5C, such as, in addition to performing demapping of the data signal and the reference signal from the FDMed signal, performing an FFT operation, performing a subcarrier demapping operation, performing an equalization operation, or performing additional receiver chain operations.

Based at least in part on the transmitting device605and the receiving device610communicating using a DFT-s-OFDM waveform communication that includes an FDMed data signal and reference signal, the transmitting device605and/or the receiving device610may conserve computing, power, network, and/or communication resources that may have otherwise been consumed traditional reference signal procedures. For example, based at least in part on the transmitting device605and the receiving device610communicating using a DFT-s-OFDM waveform communication that includes an FDMed data signal and reference signal, the transmitting device605and the receiving device610may improve channel estimation and thus communicate with a reduced error rate, which may conserve computing, power, network, and/or communication resources that may have otherwise been consumed to detect and/or correct communication errors, and/or may communicate using a reduced reference signal overhead, which may increase throughput, reduce latency, and otherwise result in more efficient usage of network resources.

FIG.7is a diagram illustrating an example process700performed, for example, by a transmitting device, in accordance with the present disclosure. Example process700is an example where the transmitting device (e.g., transmitting device605) performs operations associated with frequency domain multiplexing of a data signal and a reference signal.

As shown inFIG.7, in some aspects, process700may include generating a frequency-domain-multiplexed signal by performing frequency domain multiplexing of a data signal and a reference signal within a symbol of a DFT-s-OFDM waveform communication, the reference signal being one of a demodulation reference signal, a sounding reference signal, or a channel state information reference signal (block710). For example, the transmitting device (e.g., using communication manager906, depicted inFIG.9) may generate a frequency-domain-multiplexed signal by performing frequency domain multiplexing of a data signal and a reference signal within a symbol of a DFT-s-OFDM waveform communication, the reference signal being one of a demodulation reference signal, a sounding reference signal, or a channel state information reference signal, as described above.

As further shown inFIG.7, in some aspects, process700may include transmitting, to a receiving device, the frequency-domain-multiplexed signal (block720). For example, the transmitting device (e.g., using transmission component904and/or communication manager906, depicted inFIG.9) may transmit, to a receiving device, the frequency-domain-multiplexed signal, as described above.

In a first aspect, one of the transmitting device or the receiving device is a user equipment, and the other one of the transmitting device or the receiving device is a network node.

In a second aspect, alone or in combination with the first aspect, the transmitting device is a first UE, and the receiving device is a second UE.

In a third aspect, alone or in combination with one or more of the first and second aspects, the data signal is associated with one of a physical downlink shared channel or a physical uplink shared channel.

In a fourth aspect, alone or in combination with one or more of the first through third aspects, the data signal is DFT-precoded and the reference signal is not DFT-precoded.

In a fifth aspect, alone or in combination with one or more of the first through fourth aspects, the data signal and the reference signal are DFT-precoded.

In a sixth aspect, alone or in combination with one or more of the first through fifth aspects, process700includes selecting a density of the reference signal within the frequency-domain-multiplexed signal.

In a seventh aspect, alone or in combination with one or more of the first through sixth aspects, process700includes transmitting, to the receiving device, an indication of a density of the reference signal within the frequency-domain-multiplexed signal.

In an eighth aspect, alone or in combination with one or more of the first through seventh aspects, process700includes transmitting, to the receiving device, an indication of a frequency mapping between the data signal and the reference signal in the frequency-domain-multiplexed signal.

In a ninth aspect, alone or in combination with one or more of the first through eighth aspects, process700includes selecting a reference signal sequence associated with the frequency-domain-multiplexed signal.

In a tenth aspect, alone or in combination with one or more of the first through ninth aspects, process700includes transmitting, to the receiving device, an indication of a selected reference signal sequence associated with the frequency-domain-multiplexed signal.

In an eleventh aspect, alone or in combination with one or more of the first through tenth aspects, process700includes receiving, from the receiving device, capability information indicating a capability of the receiving device to process the frequency-domain-multiplexed signal, wherein generating the frequency-domain-multiplexed signal is based at least in part on the capability information.

In a twelfth aspect, alone or in combination with one or more of the first through eleventh aspects, process700includes selecting at least one of a density of the reference signal within the frequency-domain-multiplexed signal or a reference signal sequence associated with the frequency-domain-multiplexed signal based at least in part on a modulation and coding scheme associated with the frequency-domain-multiplexed signal.

In a thirteenth aspect, alone or in combination with one or more of the first through twelfth aspects, the frequency-domain-multiplexed signal is associated with a multiple input multiple output communication having a transmission rank, and the process700includes selecting at least one of a density of the reference signal within the frequency-domain-multiplexed signal or a reference signal sequence associated with the frequency-domain-multiplexed signal based at least in part on the transmission rank.

FIG.8is a diagram illustrating an example process800performed, for example, by a receiving device, in accordance with the present disclosure. Example process800is an example where the receiving device (e.g., receiving device610) performs operations associated with frequency domain multiplexing of a data signal and a reference signal.

As shown inFIG.8, in some aspects, process800may include receiving, from a transmitting device, a frequency-domain-multiplexed signal, the frequency-domain-multiplexed signal being associated with frequency domain multiplexing of a data signal and a reference signal within a symbol of a DFT-s-OFDM waveform communication, the reference signal being one of a demodulation reference signal, a sounding reference signal, or a channel state information reference signal (block810). For example, the receiving device (e.g., using reception component1002and/or communication manager1006, depicted inFIG.10) may receive, from a transmitting device, a frequency-domain-multiplexed signal, the frequency-domain-multiplexed signal being associated with frequency domain multiplexing of a data signal and a reference signal within a symbol of a DFT-s-OFDM waveform communication, the reference signal being one of a demodulation reference signal, a sounding reference signal, or a channel state information reference signal, as described above.

As further shown inFIG.8, in some aspects, process800may include performing demapping of the data signal and the reference signal from the frequency-domain-multiplexed signal (block820). For example, the receiving device (e.g., using communication manager1006, depicted inFIG.10) may perform demapping of the data signal and the reference signal from the frequency-domain-multiplexed signal, as described above.

In a first aspect, one of the transmitting device or the receiving device is a user equipment, and the other one of the transmitting device or the receiving device is a network node.

In a second aspect, alone or in combination with the first aspect, the transmitting device is a first UE, and the receiving device is a second UE.

In a third aspect, alone or in combination with one or more of the first and second aspects, the data signal is associated with one of a physical downlink shared channel or a physical uplink shared channel.

In a fourth aspect, alone or in combination with one or more of the first through third aspects, the data signal is DFT-precoded and the reference signal is not DFT-precoded.

In a fifth aspect, alone or in combination with one or more of the first through fourth aspects, the data signal and the reference signal are DFT-precoded.

In a sixth aspect, alone or in combination with one or more of the first through fifth aspects, process800includes receiving, from the transmitting device, an indication of a density of the reference signal within the frequency-domain-multiplexed signal, wherein demapping the data signal and the reference signal from the frequency-domain-multiplexed signal is based at least in part on the indication of the density of the reference signal within the frequency-domain-multiplexed signal.

In a seventh aspect, alone or in combination with one or more of the first through sixth aspects, process800includes receiving, from the transmitting device, an indication of a frequency mapping between the data signal and the reference signal in the frequency-domain-multiplexed signal, wherein demapping the data signal and the reference signal from the frequency-domain-multiplexed signal is based at least in part on the indication of the frequency mapping between the data signal and the reference signal in the frequency-domain-multiplexed signal.

In an eighth aspect, alone or in combination with one or more of the first through seventh aspects, process800includes receiving, from the transmitting device, an indication of a selected reference signal sequence associated with the frequency-domain-multiplexed signal, wherein demapping the data signal and the reference signal from the frequency-domain-multiplexed signal is based at least in part on the indication of the selected reference signal sequence associated with the frequency-domain-multiplexed signal.

In a ninth aspect, alone or in combination with one or more of the first through eighth aspects, process800includes transmitting, to the transmitting device, capability information indicating a capability of the receiving device to process the frequency-domain-multiplexed signal, wherein receiving the frequency-domain-multiplexed signal is based at least in part on the capability information.

FIG.9is a diagram of an example apparatus900for wireless communication, in accordance with the present disclosure. The apparatus900may be a transmitting device (e.g., transmitting device605), or a transmitting device may include the apparatus900. In some aspects, the apparatus900includes a reception component902, a transmission component904, and/or a communication manager906, which may be in communication with one another (for example, via one or more buses and/or one or more other components). In some aspects, the communication manager906is the communication manager140or the communication manager150described in connection withFIG.1. As shown, the apparatus900may communicate with another apparatus908, such as a UE or a network node (such as a CU, a DU, an RU, or a base station), using the reception component902and the transmission component904.

The communication manager906may support operations of the reception component902and/or the transmission component904. For example, the communication manager906may receive information associated with configuring reception of communications by the reception component902and/or transmission of communications by the transmission component904. Additionally, or alternatively, the communication manager906may generate and/or provide control information to the reception component902and/or the transmission component904to control reception and/or transmission of communications.

The communication manager906may generate a frequency-domain-multiplexed signal by performing frequency domain multiplexing of a data signal and a reference signal within a symbol of a DFT-s-OFDM waveform communication, the reference signal being one of a demodulation reference signal, a sounding reference signal, or a channel state information reference signal. The transmission component904may transmit, to a receiving device, the frequency-domain-multiplexed signal.

The communication manager906may select a density of the reference signal within the frequency-domain-multiplexed signal.

The transmission component904may transmit, to the receiving device, an indication of a density of the reference signal within the frequency-domain-multiplexed signal.

The transmission component904may transmit, to the receiving device, an indication of a frequency mapping between the data signal and the reference signal in the frequency-domain-multiplexed signal.

The communication manager906may select a reference signal sequence associated with the frequency-domain-multiplexed signal.

The transmission component904may transmit, to the receiving device, an indication of a selected reference signal sequence associated with the frequency-domain-multiplexed signal.

The reception component902may receive, from the receiving device, capability information indicating a capability of the receiving device to process the frequency-domain-multiplexed signal.

The communication manager906may select at least one of a density of the reference signal within the frequency-domain-multiplexed signal or a reference signal sequence associated with the frequency-domain-multiplexed signal based at least in part on a modulation and coding scheme associated with the frequency-domain-multiplexed signal.

FIG.10is a diagram of an example apparatus1000for wireless communication, in accordance with the present disclosure. The apparatus1000may be a receiving device (e.g., receiving device610), or a receiving device may include the apparatus1000. In some aspects, the apparatus1000includes a reception component1002, a transmission component1004, and/or a communication manager1006, which may be in communication with one another (for example, via one or more buses and/or one or more other components). In some aspects, the communication manager1006is the communication manager140or communication manager150described in connection withFIG.1. As shown, the apparatus1000may communicate with another apparatus1008, such as a UE or a network node (such as a CU, a DU, an RU, or a base station), using the reception component1002and the transmission component1004.

The communication manager1006may support operations of the reception component1002and/or the transmission component1004. For example, the communication manager1006may receive information associated with configuring reception of communications by the reception component1002and/or transmission of communications by the transmission component1004. Additionally, or alternatively, the communication manager1006may generate and/or provide control information to the reception component1002and/or the transmission component1004to control reception and/or transmission of communications.

The reception component1002may receive, from a transmitting device, a frequency-domain-multiplexed signal, the frequency-domain-multiplexed signal being associated with frequency domain multiplexing of a data signal and a reference signal within a symbol of a DFT-s-OFDM waveform communication, the reference signal being one of a demodulation reference signal, a sounding reference signal, or a channel state information reference signal. The communication manager1006may perform a demapping of the data signal and the reference signal from the frequency-domain-multiplexed signal.

The reception component1002may receive, from the transmitting device, an indication of a density of the reference signal within the frequency-domain-multiplexed signal.

The reception component1002may receive, from the transmitting device, an indication of a frequency mapping between the data signal and the reference signal in the frequency-domain-multiplexed signal.

The reception component1002may receive, from the transmitting device, an indication of a selected reference signal sequence associated with the frequency-domain-multiplexed signal.

The transmission component1004may transmit, to the transmitting device, capability information indicating a capability of the receiving device to process the frequency-domain-multiplexed signal.

Aspect 1: A method of wireless communication performed by a transmitting device, comprising: generating a frequency-domain-multiplexed signal by performing frequency domain multiplexing of a data signal and a reference signal within a symbol of a DFT-s-OFDM waveform communication, the reference signal being one of a demodulation reference signal, a sounding reference signal, or a channel state information reference signal; and transmitting, to a receiving device, the frequency-domain-multiplexed signal.

Aspect 2: The method of Aspect 1, wherein one of the transmitting device or the receiving device is a user equipment, and wherein the other one of the transmitting device or the receiving device is a network node.

Aspect 3: The method of Aspect 1, wherein the transmitting device is a first UE, and wherein the receiving device is a second UE.

Aspect 4: The method of any of Aspects 1-3, wherein the data signal is associated with one of a physical downlink shared channel or a physical uplink shared channel.

Aspect 5: The method of any of Aspects 1-4, wherein the data signal is DFT-precoded and wherein the reference signal is not DFT-precoded.

Aspect 6: The method of any of Aspects 1-4, wherein the data signal and the reference signal are DFT-precoded.

Aspect 7: The method of any of Aspects 1-6, further comprising selecting a density of the reference signal within the frequency-domain-multiplexed signal.

Aspect 8: The method of any of Aspects 1-7, further comprising transmitting, to the receiving device, an indication of a density of the reference signal within the frequency-domain-multiplexed signal.

Aspect 9: The method of any of Aspects 1-8, further comprising transmitting, to the receiving device, an indication of a frequency mapping between the data signal and the reference signal in the frequency-domain-multiplexed signal.

Aspect 10: The method of any of Aspects 1-9, further comprising selecting a reference signal sequence associated with the frequency-domain-multiplexed signal.

Aspect 11: The method of any of Aspects 1-10, further comprising transmitting, to the receiving device, an indication of a selected reference signal sequence associated with the frequency-domain-multiplexed signal.

Aspect 12: The method of any of Aspects 1-11, further comprising receiving, from the receiving device, capability information indicating a capability of the receiving device to process the frequency-domain-multiplexed signal, wherein generating the frequency-domain-multiplexed signal is based at least in part on the capability information.

Aspect 13: The method of any of Aspects 1-12, further comprising selecting at least one of a density of the reference signal within the frequency-domain-multiplexed signal or a reference signal sequence associated with the frequency-domain-multiplexed signal based at least in part on a modulation and coding scheme associated with the frequency-domain-multiplexed signal.

Aspect 14: The method of any of Aspects 1-13, wherein the frequency-domain-multiplexed signal is associated with a multiple input multiple output communication having a transmission rank, and wherein the method further comprises selecting at least one of a density of the reference signal within the frequency-domain-multiplexed signal or a reference signal sequence associated with the frequency-domain-multiplexed signal based at least in part on the transmission rank.

Aspect 15: A method of wireless communication performed by a receiving device, comprising: receiving, from a transmitting device, a frequency-domain-multiplexed signal, the frequency-domain-multiplexed signal being associated with frequency domain multiplexing of a data signal and a reference signal within a symbol of a DFT-s-OFDM waveform communication, the reference signal being one of a demodulation reference signal, a sounding reference signal, or a channel state information reference signal; and demapping the data signal and the reference signal from the frequency-domain-multiplexed signal.

Aspect 16: The method of Aspect 15, wherein one of the transmitting device or the receiving device is a user equipment, and wherein the other one of the transmitting device or the receiving device is a network node.

Aspect 17: The method of Aspect 15, wherein the transmitting device is a first UE, and wherein the receiving device is a second UE.

Aspect 18: The method of any of Aspects 15-17, wherein the data signal is associated with one of a physical downlink shared channel or a physical uplink shared channel.

Aspect 19: The method of any of Aspects 15-18, wherein the data signal is DFT-precoded and wherein the reference signal is not DFT-precoded.

Aspect 20: The method of any of Aspects 15-18, wherein the data signal and the reference signal are DFT-precoded.

Aspect 21: The method of any of Aspects 15-20, further comprising receiving, from the transmitting device, an indication of a density of the reference signal within the frequency-domain-multiplexed signal, wherein demapping the data signal and the reference signal from the frequency-domain-multiplexed signal is based at least in part on the indication of the density of the reference signal within the frequency-domain-multiplexed signal.

Aspect 22: The method of any of Aspects 15-21, further comprising receiving, from the transmitting device, an indication of a frequency mapping between the data signal and the reference signal in the frequency-domain-multiplexed signal, wherein demapping the data signal and the reference signal from the frequency-domain-multiplexed signal is based at least in part on the indication of the frequency mapping between the data signal and the reference signal in the frequency-domain-multiplexed signal.

Aspect 23: The method of any of Aspects 15-22, further comprising receiving, from the transmitting device, an indication of a selected reference signal sequence associated with the frequency-domain-multiplexed signal, wherein demapping the data signal and the reference signal from the frequency-domain-multiplexed signal is based at least in part on the indication of the selected reference signal sequence associated with the frequency-domain-multiplexed signal.

Aspect 24: The method of any of Aspects 15-23, further comprising transmitting, to the transmitting device, capability information indicating a capability of the receiving device to process the frequency-domain-multiplexed signal, wherein receiving the frequency-domain-multiplexed signal is based at least in part on the capability information.

Aspect 27: An apparatus for wireless communication, comprising at least one means for performing the method of one or more of Aspects 1-24.