The disclosure provides a method for measuring a power of a non-constant envelope modulated signal, an electronic device, and a computer readable storage medium. The method includes: sampling baseband I/Q data transmitted by a device under test to obtain sample data, in which a sampling duration is less than a length of a cycle of the non-constant envelope modulated signal; calculating a sample power within the sampling duration based on the sample data; matching in predetermined baseband I/Q data in the cycle based on the sample data to obtain a target baseband I/Q data segment; obtaining a power calibration value corresponding to the target baseband I/Q data segment; and obtaining an actual power of the non-constant envelope modulated signal in the cycle based on the power calibration value corresponding to the target baseband I/Q data segment and the sample power within the sampling duration.

A signal compensation device is disclosed. The signal compensation device includes an operation circuit and a modulation circuit. The operation circuit is configured to generate a control signal according to a first data signal and a second data signal, in which the second data signal is generated according to the first data signal by a signal conversion circuit. The modulation circuit is configured to provide a loop gain according to the control signal to compensate an attenuation of the signal conversion circuit.

Methods, systems, and devices for wireless communications are described. A first device and a second device may communicate via a channel. The first device may generate and transmit a reference signal, which may be a distortion probing reference signal with a high peak to average power ratio. In one implementation, the first device may use the reference signal as an input for a neural network model to learn a nonlinear response of the second device transmission components. In another implementation, the second device may sample the generated reference signal, and use the samples as inputs for a neural network model to learn the nonlinear response. The first device and the second device may exchange signaling based on learning the nonlinear response, and each device may compensate for the nonlinear response when communicating via the channel.

A method for determining a signal propagation time mismatch in a modulator comprises generating a predetermined signal shape of a amplitude component of a radio frequency signal generating one or more predetermined conditions in a frequency component of the radio frequency signal at a first time interval relative to the predetermined signal shape and detecting the one or more predetermined conditions in the frequency component at a second time interval. The method further includes determining the amplitude component at the second time interval and calculating a signal propagation time mismatch value based on the signal shape of the amplitude component, on the first time interval and the second time interval.

An apparatus for use in a polar transmitter to perform distortion estimation and compensation is provided. The apparatus includes a mixing unit, a signal processing unit, an estimation unit and a compensation unit. The mixing unit is configured to mix a test output signal and a frequency down-converting signal to generate a mixed signal. The processing unit is configured to perform signal processing on the mixed signal to generate a processed signal. The estimation unit is configured to perform distortion estimation on the processed signal to generate a distortion estimation result. The compensation unit is configured to perform pre-distortion compensation on input signals of the polar transmitter according to the distortion estimation result.

An example system comprises a first antenna and a modem. The first antenna is configured to receive a signal from a transmitting radio frequency unit. The signal includes data and a known sequence. The modem is configured to retrieve the known sequence from the signal, transform the known sequence and the data into a frequency domain, calculate averages of groups of neighboring frequency points in the frequency domain to reduce the effect of nonlinear noise in the signal, the neighboring frequency points corresponding to the preamble in the frequency domain, compare the calculated averages to an expected frequency response in the frequency domain, determine a correction filter to apply to the data based on the comparison, apply the correction filter on the data in the frequency domain to create corrected data, transform the corrected data from the frequency domain to the time domain, and provide the data.

A transmitter includes: a modulation circuit that modulates a data sequence using QAM by mapping the data sequence to only four symbols each of which differs in phase by 90 degrees from an adjacent one of the four symbols and at least two of which have different amplitudes; and a transmission circuit that wirelessly transmits the data sequence mapped to the four symbols through the modulation by the modulation circuit, by assigning the data sequence mapped to the four symbols through the modulation by the modulation circuit to different subcarriers for Orthogonal Frequency Division Multiplexing (OFDM).

A data transmission method includes generating a physical layer data frame, where the physical layer data frame includes data on which probability non-uniform modulation is performed and indication information, where the indication information indicates demodulation parameters for performing probability non-uniform demodulation on the data, where the demodulation parameters include a modulation scheme for probability non-uniform modulation, a modulation order for probability non-uniform modulation, and at least one of a probability of each constellation symbol on which probability non-uniform modulation is performed, or a mapping relationship between each constellation symbol on which probability non-uniform modulation is performed and a bit stream, sending the physical layer data frame to a receive end, receiving the physical layer data frame, determining the demodulation parameters based on the indication information, and performing probability non-uniform demodulation on the data based on the demodulation parameters.

Fiber, cable, and wireless data channels are typically impaired by reflectors and other imperfections, producing a channel state with echoes and frequency shifts in data waveforms. Here, methods of using OTFS pilot symbol waveform bursts to automatically produce a detailed 2D model of the channel state are presented. This 2D channel state can then be used to, optimize data transmission. For wireless data channels, an even more detailed 2D model of channel state can be produced by using polarization and multiple antennas in the process. Once 2D channel states are known, the system turns imperfect data channels from a liability to an advantage by using channel imperfections to boost data transmission rates. The methods can be used to improve legacy data transmission modes in multiple types of media, and are particularly useful for producing new types of robust and high capacity wireless communications using non-legacy OTFS data transmission methods.

A system for enabling signal penetration into a building includes first circuitry, located on an exterior of the building, for transmitting and receiving signals at a first frequency that experience losses when penetrating into an interior of the building, converting the received signals at the first frequency into a first format that overcome losses caused by penetrating into the interior of the building over a wireless communications link and converting received signals in the first format into the signals in the first frequency. The first circuitry receives the signals at the first frequency that are transmitted to the first circuitry using beam forming and beam steering. A first antenna associated with the first circuitry transmits the signals in the first format into the interior of the building via a wireless communications link and receives signals from the interior of the building in the first format via the wireless communications link. Second circuitry, located on the interior of the building and communicatively linked with the first circuitry via the wireless communications link, receives and transmits the converted received signals in the first format that counteracts the losses caused by penetrating into the interior of the building from/to the first circuitry. A second antenna associated with the second circuitry transmits the signals in the first format to the exterior of the building via the wireless communications link and receives signals from the exterior of the building in the first format via the wireless communications link.