PAPR suppression includes a first clipping module and a second clipping module. The second clipping module outputs, to the first clipping module, a to-be-clipped signal that satisfies an input condition of the first clipping module, where the input condition includes a peak distribution feature of an input signal. The first clipping module performs first clipping processing on the to-be-clipped signal to obtain a first clipped signal. PAPR suppression is performed based on collaboration between the two clipping modules.

Apparatuses, methods, and systems for per carrier scaling of a cancellation pulse of a multi-carrier signal are disclosed. One method includes identifying a target PAPR (peak to average power ratio) for the multi-carrier signal, identifying a target EVM (error vector magnitude) for each of cj carriers of the multi-carrier signal, setting a scaling factor for each of the cj carrier to an initial value, or each carrier cj adjusting the scaling factor for the carrier cj until a measured EVM of the carrier cj satisfies the target EVM for the subcarrier cj while maintaining the PAPR target for the multi-carrier signal, and the cancellation pulse of the multi-carrier signal with the adjusted scaling factor for each of the cj carriers.

Methods, systems and device for achieving synchronization in an orthogonal time frequency space (OTFS) signal receiver are described. An exemplary signal reception technique includes receiving an OTFS modulated wireless signal comprising pilot signal transmissions interspersed with data transmissions, calculating autocorrelation of the wireless signal using the wireless signal and a delayed version of the wireless signal that is delayed by a pre-determined delay, thereby generating an autocorrelation output, processing the autocorrelation filter through a moving average filter to produce a fine timing signal. Another exemplary signal reception technique includes receiving an OTFS modulated wireless signal comprising pilot signal transmissions interspersed with data transmissions, performing an initial automatic gain correction of the received OTFS wireless signal by peak detection and using clipping information, performing coarse automatic gain correction on results of a received and initial automatic gain control (AGC)-corrected signal.

This disclosure provides methods, devices and systems for reducing PAPR in wireless communications. Some implementations more specifically relate to suppressing the amplitudes of a data signal that exceed a threshold amplitude level. In some implementations, a transmitting device may detect one or more peaks associated with a data signal to be transmitted to a receiving device. A peak may be any sample of a data signal having an amplitude that exceeds a threshold amplitude level. The transmitting device generates peak suppression information indicating the amplitude, a phase and a position of each of the samples associated with the detected peaks. The transmitting device adjusts the data signal by reducing the amplitudes associated with the detected peaks and transmits the adjusted data signal, with the peak suppression information, to the receiving device. In some implementations, the transmitting device may compress the peak suppression information to reduce the overhead of the transmission.

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.

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.

A method of recovering information encoded by a modulated sinusoidal waveform having first, second, third and fourth data notches at respective phase angles, where a power of the modulated sinusoidal waveform is reduced relative to a power of an unmodulated sinusoidal waveform within selected ones of the first, second, third and fourth data notches so as to encode input digital data. The method includes receiving the modulated sinusoidal waveform and generating digital values representing the modulated sinusoidal waveform. A digital representation of the unmodulated sinusoidal waveform is subtracted from the digital values in order to generate a received digital data sequence, which includes digital data notch values representative of the amplitude of the modulated sinusoidal waveform within the first, second, third and fourth data notches. The input digital data is then estimated based upon the digital data notch values.

A method comprising: obtaining a first radio signal and a second radio signal, determining a first envelope signal based on the first radio signal and a second envelope signal based on the second radio signal, determining a preview envelope signal based on the first envelope signal and the second envelope signal, determining a common clipping gain signal based on the preview envelope signal, determining a first clipping gain signal based on the common clipping gain signal and a first weighing factor, determining a second clipping gain signal based on the common clipping gain signal and a second weighing factor, performing a first crest factor reduction for the first radio signal utilizing the first clipping gain signal, and performing a second crest factor reduction for the second radio signal utilizing the second clipping gain 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.

A phase tracking reference signal (PTRS) may be enhanced to carry data encoded with a relative low modulation and coding scheme (MCS). A receive device may receiving a data channel, the data channel including a transport block encoded using a first MCS. The receiving device may receiving a PTRS interleaved with the data channel. The PTRS is encoded with the second MCS that is lower than the first MCS. The receiving device may decode the PTRS to determine PTRS data. The receiving device may track phase noise using the PTRS data as a transmitted sequence of the PTRS. The receiving device may decode the transport block for the data channel based on the first MCS and the tracked phase noise.