Methods related to wireless communication systems and reducing peak-to-average-power ratio (PAPR) in MU-MIMO transmissions are provided. A base station (BS) generates a plurality of communication signals including data for a plurality of user equipment (UE) devices in a plurality of serving beam subspaces. The BS may also generate a peak-to-average-power ratio (PAPR) reduction signal for one or more of the plurality of communication signals. A first portion of the PAPR reduction signal is in a first serving beam subspace of the plurality of serving beam subspaces based on a first error vector magnitude (EVM) associated with a first UE of the plurality of UEs. A second portion of the PAPR reduction signal is in a non-serving beam subspace. The BS may also transmit, to the plurality of UEs, the plurality of communication signals and the PAPR reduction signal. Other features are also claimed and described.

Methods and apparatuses for signal processing at base station are disclosed. According to an embodiment, a digital unit (DU) compresses a block of baseband signal samples. The DU determines whether valley increment is to be applied on decompressed block of baseband signal samples by a radio unit (RU) connected with the DU, based on the compressed block. When determining that valley increment is not to be applied, the DU generates an indication for indicating not to apply valley increment. When determining that valley increment is to be applied, the DU determines information related to bit loss due to the compression. The DU sends, to the RU, the compressed block and the indication or the information related to bit loss.

Techniques for peak-to-average power ratio (PAPR) reduction are described. Wireless devices may provide signaling with respect to one or more PAPR shaping resources. For example, a wireless device may provide signaling of PAPR shaping capability information. PAPR shaping capability information may include information regarding one or more PAPR shaping resources the wireless device has a capability to implement. Additionally or alternatively, a wireless device may provide signaling of PAPR shaping information. PAPR shaping information may include information regarding shaping the signal by a wireless device prior to transmission in a communication link by implementing one or more PAPR shaping resources. Other aspects and features are also claimed and described.

Techniques for peak-to-average power ratio (PAPR) reduction are described. Wireless devices may use one or more PAPR shaping resources, such as expanded bandwidth and/or pulse-shaping filtering, for shaping a signal to reduce PAPR. For example, expanded bandwidth may be utilized for adding a cyclic affix (CA), such as may comprise a cyclic prefix (CP), cyclic suffix (CS), etc., and combinations thereof, to a frequency domain data signal to provide a CP augmented frequency domain data signal used to generate a reduced PAPR time domain data signal. Additionally or alternatively, pulse-shaping filtering may be applied to a frequency domain signal to provide a pulse-shaped frequency domain data signal used to generate a reduced PAPR time domain data signal. Other aspects and features are also claimed and described.

An electronic device may include a baseband processor and P antenna elements. The antenna elements may concurrently convey signals within M signal beams. The baseband processor may have a demultiplexer that receives a stream of M symbols. The processor may have M parallel data paths coupled between the demultiplexer and a beam former. The beam former may be coupled to amplifier circuitry over P parallel data paths. Inverse fast Fourier transformers (IFFTs) may be interposed on the M parallel data paths. A feedback path may be coupled between the M parallel data paths and the P parallel data paths. Crest factor reduction (CFR) circuitry may be interposed on the feedback path. The CFR circuitry may perform CFR operations on signals from the P parallel data paths iteratively and concurrently. This may minimize PAR in the system while supporting concurrent transmission of radio-frequency signals in multiple signal beams.

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

A system that incorporates aspects of the subject disclosure may perform operations including, for example, receiving, via an antenna, a signal generated by a communication device, detecting passive intermodulation interference in the signal, the interference generated by one or more transmitters unassociated with the communication device, and the interference determined from signal characteristics associated with a signaling protocol used by the one or more transmitters. Other embodiments are disclosed.

This disclosure provides a carrier signal processing method and apparatus. In the method, clipping factors are determined based on scheduling information corresponding to at least two respective carrier signals in a first time unit, the clipping factors correspond to the at least two respective carrier signals in the first time unit and are used for clipping processing a combination signal of the at least two carrier signals in the first time unit. The at least two carrier signals and the clipping factors are sent to a radio unit for processing. In this solution, clipping factors are matched in real time with scheduling information respectively corresponding to a plurality of carrier signals in the first time unit, to improve clipping performance.

A method for crest factor reduction (CFR). The method includes: generating a signal, x.sub.s(t); generating a vector, x(t), of size N×1 based on x.sub.s(t), wherein N>1; generating a clipping signal vector, z(t), based on x(t), wherein z(t) is a vector of size N×1; producing a transformed signal vector, y(t), based on z(t), wherein y(t) is a vector of size N×1; and generating an output signal vector, x.sub.p(t), based on y(t) and x(t), wherein generating x.sub.o(t) comprises subtracting y(t) from x(t) and x.sub.o(t) is a vector of size N×1.

An apparatus, method and computer program is described comprising: receiving a first signal comprising one or more carrier signals comprising a plurality of resource blocks, wherein each resource block is assigned to a unique frequency and time slot of the respective carrier signal; generating a clipping pulse by modifying said first signal; converting the clipping pulse signal into a plurality of narrowband signals, wherein each narrowband signal is a frequency slice of the clipping pulse signal; modifying the plurality of narrowband signals to generate a plurality of modified narrowband signals, wherein said modifying is controlled based on filter weights that define a level of noise to be added to the respective narrowband signals in accordance with a desired error vector magnitude distribution or clipping noise distribution.