151 results about "Predistortion" patented technology

The invention discloses a power adaptive digital pre-distortion method, system and device based on sparse GRU and a medium. The method comprises the steps that input and output signals under different powers are collected, a composite feature vector is constructed through amplitude normalization and phase alignment, and a pre-distortion training target is generated in combination with indirect learning; constructing a sparse GRU neural network, introducing L1 regularization constraint, and obtaining a sparse pre-distortion model through joint optimization of mean square error and sparse constraint; partial weight updating is realized based on power grading, and weight fusion output is carried out during power interval switching so as to complete power adaptive optimization; pruning and compressing the sparse GRU model and then deploying the sparse GRU model in a pre-distortion module to compensate the nonlinearity of the power amplifier; according to the method, the model complexity is reduced through rarefaction, the dynamic working condition stability is improved through a power adaptive mechanism, pruning compression adapts to low-power-consumption hardware, high precision, low complexity and adaptive capacity are considered, and the method is suitable for the low-power-consumption and high-performance requirements of a broadband wireless communication system.

Aspects of this disclosure relate to digital compensators, such as digital predistortion systems. Digital predistortion systems disclosed herein use a neural Volterra approach. Such digital predistortion systems can include a feature processing path comprising a feature artificial neural network, an envelope processing path, multipliers configured to multiply respective output signals of the feature processing path and the envelope processing path, and a combiner configured to generate a combined output signal based on at least output signals of the multipliers. The combined output signal is a digitally predistorted version of an input signal.

The invention relates to the technical field of radio frequency generator circuits, and provides a phase-locking frequency-stabilizing multi-core control radio frequency system, which processes I / Q signals and constructs a multi-core task allocation and cooperation mechanism through a digital baseband processing module, and performs pre-distortion processing and system scheduling. The double-closed-loop control module is used for stabilizing fundamental frequency, correcting temperature drift and compensating and adjusting frequency swing amplitude; the hybrid power amplification module is used for performing multi-stage hybrid power amplification signal processing and temperature monitoring through a driving stage and output stage combined topology; and the feedback sampling network module collects output signals in real time through a directional coupler and feeds back, adjusts and precisely controls the frequency stability according to the output signals.

Aspects of this disclosure relate to digital compensators, such as digital predistortion systems. Digital predistortion systems disclosed herein use a neural Volterra approach. Such digital predistortion systems can include a first processing path, an envelope processing path comprising an envelope artificial neural network, multipliers configured to multiply respective output signals of the first processing path and the envelope processing path, and a combiner configured to generate a combined output signal based on at least output signals of the multipliers. The combined output signal is a digitally predistorted version of the input signal.

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, an apparatus may include first transceiver hardware comprising: first processing logic configured to generate a first plurality of output streams associated with a first sub-array of antenna elements of an antenna array by applying a first inverse power-amplifier- to-antenna-array network (A-l) matrix to one or more first input streams; and a first plurality of digital predistortion (DPD) circuits that are apply first DPD to the first plurality of output streams. The apparatus may include second transceiver hardware comprising: second processing logic configured to generate a second plurality of output streams associated with a second sub-array of antenna elements of the antenna array by applying a second A-l matrix to second one or more input streams, and a second plurality of DPD circuits configured to apply second DPD to the second plurality of output streams.

A transceiver system includes a signal generator and controller circuit, a first signal converter circuit, an attenuator circuit, and a second signal converter circuit. Signal generator and controller circuit generates a transmitting baseband signal. First signal converter circuit generates a transmitting radio frequency signal according to transmitting baseband signal. Attenuator circuit generates an attenuated radio frequency signal according to transmitting radio frequency signal. Second signal converter circuit generates an attenuation range baseband reference signal according to attenuated radio frequency signal. Signal generator and controller circuit determines a first attenuation range for attenuator circuit according to attenuation range baseband reference signal when transmitting baseband signal is a dual-tone signal, and determines a second attenuation range from first attenuation range for attenuator circuit according to attenuation range baseband reference signal when transmitting baseband signal is a single-tone signal, and second attenuation range is for a pre-distortion process.

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, an apparatus may apply digital predistortion (DPD) to a wideband signal by splitting the wideband signal into respective distinct sub-bands, and inputting the respective distinct sub-bands to a multi-dimensional DPD apparatus. The multi-dimensional DPD apparatus may apply DPD based at least in part on using a multi-band DPD kernel that processes the respective distinct sub-bands. The multi-dimensional DPD apparatus may implement the multi-band DPD kernel as a DPD kernel set, and the DPD kernel set may be implemented using any combination of one or more envelope delay line components, one or more envelope selection components, one or more look-up-table (LUT) components, one or more computation delay line components, one or more computation selection components, one or more combiner components, and / or one or more adder components. Numerous other aspects are described.

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, an apparatus may include first transceiver hardware comprising: first processing logic configured to generate a first plurality of output streams associated with a first sub-array of antenna elements of an antenna array by applying a first inverse power-amplifier-to-antenna-array network (A-1) matrix to one or more first input streams; and a first plurality of digital predistortion (DPD) circuits that are apply first DPD to the first plurality of output streams. The apparatus may include second transceiver hardware comprising: second processing logic configured to generate a second plurality of output streams associated with a second sub-array of antenna elements of the antenna array by applying a second A-1 matrix to second one or more input streams, and a second plurality of DPD circuits configured to apply second DPD to the second plurality of output streams.

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, an apparatus may include first transceiver hardware comprising: first processing logic configured to generate a first plurality of output streams associated with a first sub-array of antenna elements of an antenna array by applying a first inverse power-amplifier-to-antenna-array network (A-1) matrix to one or more first input streams; and a first plurality of digital predistortion (DPD) circuits that are apply first DPD to the first plurality of output streams. The apparatus may include second transceiver hardware comprising: second processing logic configured to generate a second plurality of output streams associated with a second sub-array of antenna elements of the antenna array by applying a second A-1 matrix to second one or more input streams, and a second plurality of DPD circuits configured to apply second DPD to the second plurality of output streams.

The application provides an AM-PM distortion calibration method applied to an UWB transmitter and belongs to the field of UWB communication. The method adds a sampling resistor between a linear voltage stabilizing power supply LDO and a digital power amplifier DPA driving stage of the UWB transmitter using a digital power amplifier, so as to simulate the instantaneous change of the power supply voltage of the DPA driving stage when the UWB pulse is transmitted; an adjustable delay unit is added between a carrier input port LO and the DPA driving stage; the continuous sine wave is transmitted, the phase information under each digital baseband amplitude control word is collected to form original data of the AM-PM distortion of the UWB transmitter, the digital baseband output AM-PM control word is used to control the adjustable delay unit to output the phase which is opposite to the original data and has the same size, so that the phase predistortion of the transmitted UWB pulse is realized, and the AM-PM distortion calibration is completed. The application has the advantages of simple implementation and strong compensation capacity.

A communication device comprises: a digital predistortion (DPD) circuit; a digital-to-analog converter (DAC) configured to convert output signals of the DPD circuit into analog signals; a power amplifier configured to amplify the analog signals; and an antenna configured to transmit the amplified analog signals, wherein the DPD circuit may be configured to: generate first predistortion signals by performing a convolution operation on digital signals of a reference time unit over a time interval including a first set of time units before the reference time unit and a second set of time units after the reference time unit; generate second predistortion signals by performing predistortion on the digital signals; and generate the output signals of the DPD circuit on the basis of the first predistortion signals and the second predistortion signals.

The invention provides a digital pre-distortion coefficient updating method and device for a frequency hopping communication system, and the method comprises the steps: obtaining a corresponding historical digital pre-distortion coefficient when the system hops to a target frequency point, and collecting training data at the initial stage of a current hop; based on the historical digital pre-distortion coefficient and the training data, obtaining an intermediate vector used for representing the change degree of the system through an adaptive filtering algorithm, and determining a change metric based on the intermediate vector; comparing the change measurement with a preset threshold value so as to divide the system state change into different levels, and dynamically triggering a matched updating mode; wherein the updating mode comprises a holding mode, a lightweight tracking mode and a precise reconstruction mode. According to the method, the system state change is divided into different levels by quantitatively evaluating the change measurement of the coefficient update vector, and the update mode which is most matched with the change is dynamically triggered, so that the global optimization of the system performance and the resource overhead is realized.

The invention discloses a satellite synchronous detection signal transmitting device and applying method for an underwater large-burial-depth pipeline, and relates to the technical field of satellite synchronous detection, and the satellite synchronous detection signal transmitting device comprises a low-frequency shear force sensing module, a near-resonance recognition modeling module, a target detuning adjustment module, a pre-distortion beam generation module, a leakage spectrum suppression module and a closed-loop adaptive control module. And the low-frequency shear force sensing module is used for constructing a low-frequency shear force real-time sensing link. According to the method, through low-frequency shear force sensing, parameterized structure modeling, damping and rigidity cooperative adjustment, predistortion beam control and leakage spectrum screening, real-time prediction and active suppression of the antenna resonance risk in the deep sea environment are achieved, and the pipeline positioning precision is guaranteed. By combining satellite positioning residual error and time delay drift feedback, closed-loop adaptive control is constructed, a driving structure and signal collaborative optimization are realized, anti-resonance and leakage suppression effects are kept for a long time, an unattended operation period is prolonged, and detection reliability and data validity are improved.

This application relates to a predistortion circuit for a wireless transmitter and a method for generating a predistorted baseband signal. Specifically, the invention discloses a predistortion circuit for a wireless transmitter, comprising a signal input configured to receive a baseband signal. Furthermore, the predistortion circuit includes a predistorter configured to generate a predistorted baseband signal using the baseband signal and a selection of a first predistorter configuration and a second predistorter configuration.

The computed tomography (CT) scanner gantry rotates relative to the fixed substrate of the CT scanner. During gantry rotation, digital data is transmitted from a data source via a modulator, transmission channel, and demodulator to a data receiver between the gantry and the substrate. A predistortion device located upstream of the transmission channel predistorts the transmitted signal generated by the modulator from the data source through modulation according to a predistortion rule. Only the predistorted transmitted signal is transmitted to the transmission channel. Alternatively or additionally, a postdistortion device located downstream of the transmission channel postdistorts the signal transmitted via the transmission channel according to a postdistortion rule, and only the postdistorted signal is transmitted to the demodulator. The predistortion rule and / or postdistortion rule are repeatedly reset by a setting device during gantry rotation.

The invention relates to the technical field of radar interference high-speed transmission, in particular to an SAR (Synthetic Aperture Radar) interference method based on high-speed data transmission, which comprises the following steps of: receiving a radio-frequency signal transmitted by an interfered SAR, performing down-conversion and analog-to-digital conversion on the radio-frequency signal by a radio-frequency receiving front end to obtain an original sampling data stream, and transmitting the original sampling data stream to a programmable logic part through a high-speed serial interface; the method comprises the following steps: extracting pulse description words including pulse arrival time, pulse width, pulse repetition interval and carrier frequency, reconstructing a coherent interference signal baseband waveform in real time according to the pulse description words, and performing digital up-conversion and digital pre-distortion processing on the baseband waveform to generate a target interference intermediate frequency digital signal; and after digital-to-analog conversion and up-conversion are completed, an interference radio frequency signal is radiated. According to the method, data transmission and signal processing delay can be reduced, interference signal coherence is guaranteed, and intermediate frequency signal generation precision and processing real-time performance are improved.

The application relates to the technical field of wireless communication, and discloses a digital predistortion method for improving the linearity of a power amplifier in a phased array system, which comprises the following steps: step one, acquiring nonlinear parameters of a power amplifier under dynamic load in real time, wherein the nonlinear parameters comprise input signal amplitude and phase characteristics, temperature parameters and quantum tunneling current parameters; step two, generating a predistortion compensation signal based on the nonlinear parameters, wherein the predistortion compensation signal comprises a quantum phase compensation term and a dynamic phase change compensation term; and step three, superimposing the predistortion compensation signal to an original input signal to generate a predistortion modulation signal. The application improves the linearity of the power amplifier by introducing the quantum phase compensation term and the dynamic phase change compensation term, and improves the accuracy of predistortion compensation by accurately acquiring the nonlinear parameters in real time under the dynamic load environment.

This invention relates to a high-precision digital predistortion phase interpolator with a constant input load, comprising: a multi-phase clock generation circuit, an input buffer circuit, two pre-filter circuits, a phase interpolation core circuit, a CML2CMOS circuit, and a control code decoder circuit. The two pre-filter circuits convert two full-swing square wave signals into two sinusoidal clocks. The phase interpolation core circuit performs nonlinear interpolation on the two sinusoidal clocks with a constant input load based on two weighted control codes, outputting a small-swing signal. This phase interpolator significantly improves interpolation accuracy. Digital predistortion of the interpolation weights can be achieved by adjusting the control code decoder, further enhancing the accuracy of the phase interpolator and enabling high-speed, high-precision output clocks. It is suitable for clock data recovery circuits and phase-locked loops in high-speed SerDes systems.

The invention discloses a temperature sensing type dense gating circulation unit digital predistorter model and a design method thereof, and the method comprises the steps: introducing real-time temperature information as a key feature into the model input, and combining the time sequence modeling capability of a gating circulation unit with a dense jump connection structure, thereby obtaining a temperature sensing type dense gating circulation unit digital predistorter model. And high-precision and robust compensation of nonlinear and memory effects of the PA under different temperature working conditions is realized. The design method comprises the following steps: S1, synchronously acquiring and aligning data; s2, performing input preprocessing and framing; s3, multi-dimensional feature extraction: for each time step n in each frame, extracting an eight-dimensional feature vector Ft from the preprocessed signals Ix [n] and Qx [n] and the temperature T [n]; s4, carrying out GRU time sequence modeling and dense feature fusion; and S5, performing model deployment and an adaptive mechanism.

The invention discloses a digital pre-distortion algorithm verification method and device suitable for a large-scale antenna array, and the method comprises the steps: constructing a single-channel radio frequency link, and obtaining the input data and output data of a power amplifier; taking input data and output data of the power amplifier as a training set, and training by using a target digital pre-distortion algorithm to obtain a pre-distorter model and a pre-distorter model correlation coefficient; modeling input data and output data of a power amplifier into a high-precision mathematical model through a neural network method, loading the high-precision mathematical model into a radio frequency channel of the large-scale phased array system-level simulation model, and adding actual damage into the large-scale phased array system-level simulation model; deploying a predistorter model in a radio frequency channel of the large-scale phased array system-level simulation model, and evaluating the final performance of a target digital predistortion algorithm from multiple dimensions; modeling and digital pre-distortion training are carried out based on hardware actual measurement data, the research and development cost is reduced, and algorithm optimization and system design are guided.

Systems, methods, apparatus, and computer-readable media for power amplifier gain error compensation for a digital power amplifier (DPA) are provided.SOLUTION: A signal compensation method for digitally correcting gain characteristics of a DPA includes obtaining an in-phase (I) component and a quadrature-phase (Q) component of baseband samples corresponding to an in-phase input amplitude code and a quadrature-phase input amplitude code, distorting the in-phase input amplitude code based on first gain predistortion information corresponding to an in-phase signal branch of the DPA to generate an I-component predistorted output amplitude code, distorting the quadrature-phase input amplitude code based on second gain predistortion information corresponding to a quadrature-phase signal branch of the DPA to generate a Q-component predistorted output amplitude code, and the DPA is driven using the I-component and Q-component predistorted output amplitude codes to generate a radio frequency (RF) output.SELECTED DRAWING: Figure 17

The invention discloses a dual-mode millimeter wave radar transmitting method, a receiving method and a transceiving system, and the method comprises the steps: analyzing a received system control parameter, and obtaining a working mode selection signal and waveform parameters corresponding to different working modes; generating an intermediate frequency receiving local oscillator signal and an intermediate frequency transmitting local oscillator signal by combining a direct digital synthesis technology and an amplitude-phase predistortion compensation technology under the control of a waveform parameter corresponding to the selected working mode based on the mode selection signal; generating a receiving local oscillation source signal and a transmitting excitation source signal corresponding to the selected working mode based on the intermediate-frequency receiving local oscillation signal and the intermediate-frequency transmitting local oscillation signal; the transmitting excitation source signal is converted into a transmitting signal and is transmitted to a transmitting antenna, and the receiving local oscillation source signal is transmitted to receiving equipment; according to the invention, rapid switching between the SFMCW function and the LFMCW function can be realized with high precision.

The present application relates to a digital pre-distortion processing circuit and a signal processing device, the digital pre-distortion processing circuit comprising a narrow-band spread spectrum module, a digital pre-distortion module and a filtering module. The narrow-band spread spectrum module is used to spread the input narrow-band radio frequency signal into a wide-band radio frequency signal. The bandwidth of the wide-band radio frequency signal is a preset bandwidth. The digital pre-distortion module is used to perform digital pre-distortion linearization processing on the wide-band radio frequency signal to obtain a linearized wide-band radio frequency signal; the preset bandwidth is located within the optimal cancellation bandwidth of the digital pre-distortion module. The filtering module is used to perform signal filtering on the linearized wide-band radio frequency signal to obtain a linearized narrow-band radio frequency signal. The digital pre-distortion linearization processing on the narrow-band radio frequency signal is realized, and the cancellation capability of the digital pre-distortion system for the narrow-band radio frequency signal is greatly improved.

An electronic device for predistortion of an input signal is provided. The electronic device may include: a memory for storing instructions; a transmission antenna; a power amplifier, a digital predistortion (DPD) circuit including a first DPD path and a second DPD path; and at least one processor. The electronic device may operate to predistort a first digital signal having a first sampling rate based on the first DPD path; transmit a first output signal generated from the predistorted first digital signal; provide to the DPD circuit a control signal for activating the second DPD path based on a correlation value between the first digital signal and the first output signal; predistort a second digital signal having a second sampling rate based on the second DPD path; and transmit a second output signal generated from the predistorted second digital signal.

Various embodiments of the present disclosure relate to transmitter systems, methods, and instructions for signal predistortion. The transmitter system includes an intermodulation distortion (IMD) filter module configured to filter a detected feedback signal (Yin) to generate a targeted filtered signal (Yout), a digital pre-distortion (DPD) coefficient estimation module configured to update signal generation coefficients based on comparing an input signal (Sin) with the targeted filtered signal (Yout), and a distortion compensation processing module configured to generate a pre-distorted signal (Uout) based on the input signal (Sin) using the updated signal generation coefficients.

The invention discloses a hybrid integrated correction-free linear frequency modulation DFB laser ranging system and a ranging method thereof, and relates to the technical field of laser radar ranging. Comprising a hybrid integrated packaging module, a first DFB laser, a second DFB laser, an optical circulator unit, a GPPO high-frequency radio frequency interface and an independent regulation and control unit, the first DFB laser, the second DFB laser and the optical circulator unit are packaged in the hybrid integrated packaging module, and the GPPO high-frequency radio frequency interface is arranged on the hybrid integrated packaging module; according to the hybrid integrated correction-free linear frequency modulation DFB laser ranging system and the ranging method thereof, the sweep frequency linearity of the laser is directly anchored on a radio frequency source of an electric domain through a physical mechanism of sideband locking, so that the sweep frequency linearity of output optical frequency is ensured from the physical level; a complex digital pre-distortion algorithm or expensive photoelectric phase-locked loop hardware is thoroughly omitted, and the system complexity is greatly reduced.

An adaptable, multistage, multi-rate digital predistortion system that can increase the accuracy of the distortion applied to a power amplifier input signal is disclosed. Further, the digital predistortion system can be implemented using a reduced circuit area by reducing a number of coefficients used by the models applied to generate the distortion compensation signal. Further, the system can implement an improved digital predistortion adaptation engine that improves an adjacent channel leakage ratio of the digital predistortion system. Moreover, the system can compensate for non-linear impairments due to analog / RF circuits and systems and improve at least the following metrics: Error vector magnitude (EVM), adjacent channel leakage ratio (ACLR), spectrum emission mask (SEM), and power consumption of the circuits and systems. An example of circuits and systems is radio frequency power amplifier (RF PA).

This invention proposes a predistortion processing method for ultra-wideband spaceborne synthetic aperture radar (UWAR), solving the problem of severe degradation of the amplitude and phase characteristics of linear frequency modulated (LFM) signals within the signal band due to system errors. The method includes: constructing an ideal UWAR LFM signal based on actual system parameters; constructing a calibration closed-loop circuit within the UWAR system to obtain the actual UWAR LFM signal after distortion; calculating the amplitude and phase difference between the actual UWAR LFM signal and the ideal UWAR LFM signal to obtain the distortion error curve; fitting the error curve using a piecewise polynomial fitting method with the least squares approach; stitching together the amplitude and phase errors between adjacent fitted piecewise error curves using a sliding window weighted average method; constructing a time-domain predistortion compensation signal based on the extracted amplitude and phase errors; and inputting the predistortion compensation signal into the UWAR transmitter for compensation.

The invention discloses a laboratory sunlight energy-saving illumination management system, belongs to the technical field of energy-saving illumination, and solves the problems that a solar simulator bus is out of control due to bidirectional power conflict, an experiment is failed due to light ripple pollution, and energy conservation is more wasted. Comprising a multi-phase magnetic energy cyclic matrix module which generates a controlled multi-phase alternating current energy field; the rotating field transformer energy transfer device module is used for directionally distributing energy in a multi-phase alternating current energy field to each output channel according to a real-time instruction; the distributed virtual ground bus framework module is used for maintaining the power supply reference potential of each output channel; and the digital pre-distortion compensator module is used for performing nonlinear and memory effect compensation on an input instruction and sending the compensated instruction to the multi-phase magnetic energy cyclic matrix module. According to the invention, the rotating magnetic field is coupled with the distributed wireless energy network to decouple the power flow, the noise is suppressed, the spectrum is independent, the energy is saved, and repeated experiments are avoided.

A device may include a first model implemented using a first processing circuit configured to implement a transformation function to generate an initial predistortion signal based on an input signal corresponding to an output of a power amplifier. The device may include a second model implemented using a second processing circuit configured to implement a modification function to modify the initial predistortion signal. A device may include a configurable multiplier configured to weight an output of the second model based at least in part on a weighting value to obtain a weighted output. A device may include a combiner configured to combine the initial predistortion signal that is output by the first model with the weighted output to generate a digital predistortion signal for the power amplifier in communication with the digital predistortion system.