Abstract: Certain aspects of the present disclosure provide techniques for channel aware demodulation reference signals (DMRS). An example method, performed at a user equipment (UE), generally includes receiving a message indicating one or more parameters for dynamic DMRS resource allocation, and communicating during one or more periods using DMRS resources dynamically allocated for the one or more periods based on the one or more parameters.

Abstract: In some aspects of the systems, methods, and devices described herein, one or more asymmetric modulation constellations may be utilized. For example, a modulation constellation utilized to modulate data symbols may be asymmetric. In some approaches, an asymmetric modulation constellation may be generated by introducing a phase shift (e.g., cyclic shift, phase rotation) to one or more constellation points of a modulation constellation. An asymmetric modulation constellation may allow detecting phase shifts without ambiguity. For example, a user equipment (UE) may perform channel estimation or phase noise estimation aided by data symbols that are modulated with an asymmetric modulation constellation. In some examples, a UE may receive a message from a network entity indicating a configuration of an asymmetric modulation constellation.

Abstract: A method of wireless communication by a receiver, includes predicting, with an artificial neural network, at each data block of a set of data blocks, a least complex set of demodulator parameters that will achieve a goal, based on features of a data block expected to be received. The method also includes dynamically selecting the least complex set of demodulator parameters, from multiple sets of demodulator parameters, based on the features of the data block expected to be received. The selecting occurring to prevent degradation of demodulation performance for each data block with the selected set of demodulator parameters for the data block, with respect to a more complex set of demodulator parameters.

Abstract: Certain aspects of the present disclosure provide techniques for simulating a receiver for link adaptation. A method for wireless communications by an apparatus includes obtaining, from an UE, parameters of a UE receiver; determining channel characteristics of a communication channel between the apparatus and the UE based on a measurement of a signal received from the UE; estimating a response of the UE receiver communicating on the communication channel having the channel characteristics based on a digital representation of the UE receiver, wherein the digital representation of the UE receiver is based on the parameters of the UE receiver; determining, based on the estimated response, at least one parameter for communication on the communication channel with the UE; sending, to the UE, an indication of the at least one parameter; and communicating with the UE in accordance with the at least one parameter.

Abstract: Methods, systems, and devices for wireless communications are described. For instance, a user equipment (UE) may transmit a first report indicating a capability to support per codeword demodulation for a set of codewords, a second type of demodulation for the set of codewords, or both. The UE may receive, based on transmitting the first report, the set of codewords over a set of spatial streams in accordance with the per codeword demodulation or the second type of demodulation. The UE may transmit a second report indicating a capacity ratio metric for each codeword of the set of codewords based on receiving the set of codewords over the set of spatial streams in accordance with the per codeword demodulation or the second type of demodulation.

Abstract: Methods, systems, and devices for fast beam selection via user equipment (UE) receive (Rx) beam selection reporting are described. A UE may transmit a beam selection report conveying a selected Rx beam, position, and orientation to a network entity. The network entity may build a database with the conveyed information. The network entity may “tag” each position for which a UE has transmitted a beam selection report and, if another UE gets close to a “tagged” position, the network entity may indicate the associated position, orientation, selected Rx beam, and a corresponding transmit (Tx) beam to that UE. The UE may use the information to select Tx and Rx beam search windows and window centers. Compared to other methods, the process described herein may result in a smaller search window, decreased complexity of the beam selection process, decreased power consumption, decreased latency, and more accurate tracking of UE dynamics.

Abstract: Methods, systems, and devices for wireless communications are described. A user equipment (UE) may transmit neural network (NN) capability information to a network entity. The network entity may train the NN model by selecting a NN-based precoder and generating associated coefficients. The network entity may transmit an indication of the precoder coefficients to the UE. The network entity may transmit demodulation reference signals (DMRSs) that have not been precoded and a physical downlink shared channel (PDSCH) signal that has been narrowband-precoded according to the indicated precoder. The UE may then perform and input a channel estimation to the NN model. The NN model may output the narrowband precoder, which the UE may use to generate a narrowband channel estimate and demodulate the narrowband precoded PDSCH signal. In some examples, the network entity may update NN coefficients and may indicate the updated NN coefficients to the UE.

Abstract: Methods, systems, and devices for wireless communications are described. A user equipment (UE) may transmit neural network (NN) capability information to a network entity. The network entity may train the NN model by selecting a NN-based precoder and generating associated coefficients. The network entity may transmit an indication of the precoder coefficients to the UE. The network entity may transmit demodulation reference signals (DMRSs) that have not been precoded and a physical downlink shared channel (PDSCH) signal that has been narrowband-precoded according to the indicated precoder. The UE may then perform and input a channel estimation to the NN model. The NN model may output the narrowband precoder, which the UE may use to generate a narrowband channel estimate and demodulate the narrowband precoded PDSCH signal. In some examples, the network entity may update NN coefficients and may indicate the updated NN coefficients to the UE.

Abstract: Methods, systems, and devices for wireless communications are described. A user equipment (UE) may receive, within a subframe, a plurality of sidelink control channel signals providing scheduling information for a plurality of sidelink shared channel signals that are also received within the subframe. The UE may determine to use one or more of the plurality of sidelink control channel signals as pilot signals for decoding the plurality of sidelink shared channel signals. The UE may decode the plurality of sidelink shared channel signals based at least in part on the plurality of sidelink control channel signals as pilot signals.

Abstract: Certain aspects of the present disclosure provide techniques for wireless communications by an apparatus. Certain techniques include sending an indication that the apparatus is capable of supporting lattice reduction (LR) demodulation; receiving a first LR transformation matrix (to be used for demodulating a modulated signal); and receiving the modulated signal.

Abstract: Certain aspects of the present disclosure provide techniques for wireless communications by an apparatus. Certain techniques include sending an indication that the apparatus is capable of supporting lattice reduction (LR) demodulation; receiving a first LR transformation matrix (to be used for demodulating a modulated signal); and receiving the modulated signal.

Abstract: Methods, systems, and devices for wireless communications are described. A transmitting device or a receiving device may indicate support for crest factor reduction (CFR) techniques using clipping and mirroring. The transmitting device may indicate a clipping level and a mirroring level for a CFR function. The transmitting device may generate a waveform in accordance with the CFR function and may transmit the waveform to the receiving device. The receiving device may monitor the waveform to detect one or more mirrored portions of the waveform. The receiving device may invert the one or more mirrored portions of the waveform over the mirroring level to restore and decode the waveform.

Abstract: Methods, systems, and devices for wireless communications are described. A transmitting device or a receiving device may indicate support for crest factor reduction (CFR) techniques using clipping and mirroring. The transmitting device may indicate a clipping level and a mirroring level for a CFR function. The transmitting device may generate a waveform in accordance with the CFR function and may transmit the waveform to the receiving device. The receiving device may monitor the waveform to detect one or more mirrored portions of the waveform. The receiving device may invert the one or more mirrored portions of the waveform over the mirroring level to restore and decode the waveform.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a transmitting device may generate a waveform having an original amplitude. The transmitting device may reduce a peak portion of the original amplitude that is above a mirror level according to a reduction function that is based at least in part on a difference function associated with a difference between the mirror level and the peak portion, to obtain a reduced peak amplitude for the waveform. The transmitting device may transmit the waveform with the reduced peak amplitude. Numerous other aspects are described.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may transmit an indication of a preprocessing matrix to be applied to received communications. The UE may receive a communication having precoding applied, the precoding based at least in part on the preprocessing matrix. Numerous other aspects are described.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may determine that a measurement associated with signal strength satisfies a threshold. The UE may modify a parameter associated with a modem of the UE, based at least in part on the measurement satisfying the threshold, to reduce power consumption. Numerous other aspects are described.

Abstract: Apparatus, methods, and computer program products for wireless communication are provided. An example method may include receiving a communication from a second wireless device. The example method may further include demodulating the communication based on a combination of lattice reduction (LR) and per-stream recursive demapping (PSRD).

Abstract: Methods, systems, and devices for wireless communications are described. Generally, the described techniques provide for flexible selection of a type of mapping to use for mapping code blocks to a set of resources for transmission. A user equipment (UE) may transmit assistance information to a base station to assist the base station in selecting from a set of mapping types available for code block mapping. The UE may then receive, from the base station, an indication of a selected mapping type for code block mapping based on the assistance information. The assistance information may include a recommendation of a mapping type or a metric of a channel that the base station may use to select the mapping type. Because the mapping type may be selected dynamically (e.g., “on the fly”), the UE and the base station may be able to adaptively exploit different types of diversity.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may transmit, to a network node, supported receiver type information including a list of one or more receiver types supported by the UE. The UE may receive, from the network node, an indication of one or more selected receiver types, from the one or more receiver types supported by the UE, to be used for receiving one or more portions of a downlink communication. The UE may receive, from the network node, the one or more portions of the downlink communication using the one or more selected receiver types. Numerous other aspects are described.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a transmitting device may generate a waveform having an original amplitude. The transmitting device may reduce a peak portion of the original amplitude that is above a mirror level according to a reduction function that is based at least in part on a difference function associated with a difference between the mirror level and the peak portion, to obtain a reduced peak amplitude for the waveform. The transmitting device may transmit the waveform with the reduced peak amplitude. Numerous other aspects are described.