H04L27/2623

Achieving synchronization in an orthogonal time frequency space signal receiver

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.

Enhanced phase tracking reference signal

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.

CFR ERROR DEPOSITION OUT OF THE TRANSMISSION BAND

An apparatus comprises a digital processing device configured to generate a digital transmission signal, a digital-to-analog converter connected to the digital processing device and configured to convert the digital transmission signal into an analog transmission signal, and a power amplifier connected to the digital-to-analog converter and configured to amplify the analog transmission signal. An antenna filter is connected to the power amplifier and configured to filter the amplified analog transmission signal; the antenna filter is configured to pass frequencies in at least one passband and to attenuate frequencies in at least one stopband. The digital processing device is configured to perform a process of reducing peak power in the digital transmission signal; in this process error components having different frequencies are produced. A frequency spectrum of the error components is manipulated such that a part of the error components is deposited in the stopband of the antenna filter.

RECEIVER ARCHITECTURE FOR LINEAR MODULATION BASED COMMUNICATION SYSTEMS

A receiver for Filter Bank Multicarrier frequency spread signals such as FBMC, FBMC/OQAM, OFDM, comprises a linear phase rotation module adapted to introduce a linear phase rotation to a received time domain signal, a discrete Fourier transform and a Finite Impulse response digital filter. The coefficients of the digital filter define a shift of the frequency response of the prototype filter of the receiver, and the coefficients of the digital filter are fixed so as to compensate the linear phase rotation introduced by the filter. The frequency shift introduced may be equal to the reciprocal of a power of two of the modulation sub carrier spacing.

Peak suppression information multiplexing on downlink shared channel

A base station may multiplex a peak suppression information message (PSIM) on a physical downlink shared channel (PDSCH) with data for efficient implementation of PSIMs for peak to average power ratio (PAPR) reduction. A base station may clip peaks from a signal to be transmitted and capture information of the clipped peaks into a PSIM. The base station may then multiplex the PSIM on the PDSCH such that a receiving device (for example, a user equipment (UE)) may receive the signal and reconstruct the signal (for example, PDSCH data) using the PSIM. According to some aspects, each PDSCH symbol may include a PSIM for a previous PDSCH symbol, or the PSIM may be for the current symbol. Various aspects of the techniques described herein may further provide for PSIM positioning in frequency, PSIM modulation, PSIM channel coding, PSIM multiple-input multiple-output (MIMO) configurations, among other examples.

Technique for PAPR Reduction in Communication Channel
20170353340 · 2017-12-07 ·

A technique of mapping data, suitable for Peak to Average Power Ratio (PAPR) reduction while transmitting data portions via a communication channel limited by a peak power p.sub.peak. The mapping is performed by utilizing a Markovian symbol transition probability distribution with quantized probabilities and by selecting, for a specific data portion at a current channel state, such a binary symbol (called thinned label) which allows puncturing one or more bits in the thinned label's bit sequence before transmission.

NOISE-SHAPING CREST FACTOR REDUCTION (CFR) METHODS AND DEVICES
20170331650 · 2017-11-16 ·

Embodiments of a noise-shaping crest factor reduction method for a carrier signal (and a device that performs the method) include (a) clipping the carrier signal by selecting at least one carrier signal peak that has a magnitude exceeding a predetermined crest factor reduction threshold, (b) subtracting the resulting clipped signal from the carrier signal, (c) confining, by a noise shaping filter, the resulting clipping noise signal in a frequency band corresponding to that of the carrier signal, and (d) subtracting the resulting spectrally shaped clipping noise signal from a delayed version of the carrier signal. The confining process includes selecting first sub-areas of the noise shaping filter response at one or more guard bands, selecting at least one second sub-area of the noise shaping filter response elsewhere in the frequency band, and setting the first sub-areas to a first predetermined magnitude higher than the magnitude of the second sub-area.

Communication device with power amplifier crest factor reduction

Various embodiments include a power amplifier with crest factor reduction embodied by first circuitry for producing a correlated out-of-band noise signal for controlling the adjacent channel leakage ratio (ACLR) of a communication device; and second circuitry for providing an output signal for controlling the error vector magnitude (EVM) of a digital radio. The ACLR and the EVM are concurrently individually controllable. Additional apparatus is described.

Techniques for ADC clipping rate based LNA gain value modification
11490451 · 2022-11-01 · ·

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a receiver device may identify an analog to digital converter (ADC) clipping rate for one or more measurement windows. The receiver device may modify, based at least in part on a determination that the ADC clipping rate does not satisfy a threshold, a low noise amplifier (LNA) gain value to be used by the receiver device. The receiver device may receive a signal using the modified LNA gain value. Numerous other aspects are provided.

Signal Clipping Processing Method and Device
20170302490 · 2017-10-19 ·

A signal clipping processing method and a device, the method including performing peak detection on an input signal, so as to obtain amplitude information, phase information, and location information of a peak signal of the input signal; obtaining, according to amplitude information and phase information of each peak signal, a peak forming factor corresponding to each peak signal, and separately outputting, according to location information of each peak signal, a corresponding cancellation pulse sequence; and calculating a sum of products of peak forming factors corresponding to all peak signals and cancellation pulse sequences corresponding to all the peak signals, so as to obtain a clipping noise, and using a difference between the input signal and the clipping noise as a signal obtained after clipping processing.