309 results about "Predistortion" patented technology

This disclosure describes an auto-calibration of mixers in a quantum orchestration platform. Predistortion is computed according to an RF signal that is downconverted with a local oscillator tone that is offset from an upconverter tone. Three tones present in the original RF signal are distinguished and used to construct a cost function. The minimization of the cost function is used to cancel an unwanted LO leakage and an image tone. Because the quantum orchestration platform generates both the unconverted IQ signals and the cost function for their optimization, the optimization can be performed in real time inside a single device without the need to communicate with external devices. This allows for the optimization of single sideband upconverted signals in a fraction of the time it typically takes using distributed systems employing separate waveform generators and spectrum analyzers.

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.

The invention discloses a time delay compensation control method and system for two-way communication of a repeater, particularly relates to the technical field of repeaters, and is used for solving the problem of signal time delay distortion caused by polarization mode dispersion in an optical fiber link. By using polynomial fitting and a frequency domain interpolation algorithm and combining a polarization state time delay spectrum chaos degree index and a phase high-order dynamic variable rate index, the complexity of the model is dynamically adjusted, an accurate nonlinear time delay model is generated, and the defect of nonlinear time delay modeling in a traditional method is overcome; the time delay compensation amount is reversely calculated based on the model and mapped into a phase predistortion parameter, a full-band time delay gradient compensation matrix is formed, and the time delay dispersion effect in an optical fiber link is effectively compensated through phase predistortion; therefore, the flattening correction of the broadband signal time delay is realized, the demodulation performance of the receiving end signal is improved, the communication quality of the repeater in a high-frequency and large-bandwidth scene is ensured, and the high-precision service requirement is met.

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.

Method and device(s) for supporting performance of machine learning based CFR and DPD on multiple digital input signals relating to different frequency bands, respectively, in order to signal condition said signals before power amplification and subsequent transmission in said frequency bands by a wireless communication network. The device(s) obtain said multiple digital input signals as complex valued signals. The device(s) perform feature construction that takes said multiple digital input signals as input and provides constructed feature signals according to predefined constructed feature types as output. Said predefined constructed feature types relate to at least the following per complex valued sample of the obtained complex valued multiple digital input signals the real part of the sample, the imaginary part of the sample and at least one of the absolute value of the sample and the phase of the sample.

The invention relates to the technical field of wireless communication, and discloses a digital pre-distortion method for improving the linearity of a power amplifier in a phased array system, which comprises the following steps of: 1, acquiring a nonlinear parameter of the power amplifier under a dynamic load in real time, the nonlinear parameters comprise an input signal amplitude-phase characteristic, a temperature parameter and a quantum tunneling current parameter; 2, generating a pre-distortion compensation signal based on the nonlinear parameter, wherein the pre-distortion compensation signal comprises a quantum phase compensation item and a dynamic phase change compensation item; and step 3, superposing the pre-distortion compensation signal to an original input signal to generate a pre-distortion modulation signal. The linearity of the power amplifier is improved by introducing the quantum phase compensation item and the dynamic phase change compensation item, nonlinear parameters are accurately obtained in real time in a dynamic load environment, and the precision of pre-distortion compensation is improved.

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.

A radio-frequency (RF) circuit including: a multi-tone generation circuit configured to generate a multi-tone signal including a plurality of tones; a predistortion circuit configured to predistort the multi-tone signal or a modulation signal and output a predistortion signal; a power amplifier configured to amplify the predistortion signal and output an output signal; and a predistortion modeling circuit configured to model a predistortion model corresponding to the predistortion circuit based on the predistortion signal corresponding to the multi-tone signal and the output signal.

The invention belongs to the technical field of signal processing, and particularly discloses a deep learning driven power amplifier predistortion method, which comprises the following steps: constructing a signal matrix of a target signal sequence, the target signal sequence being obtained by preprocessing an original time signal sequence collected from a signal source; sequentially inputting the signal matrix into a PDTRANS predistortion model and a power amplifier, and obtaining an output signal sequence of the power amplifier; determining a loss function value based on the output signal sequence and the target signal sequence, and adjusting hyper-parameters of a PDTRANS pre-distortion model based on the loss function value; the steps of obtaining the output signal sequence of the power amplifier and adjusting the hyper-parameters of the PDTRANS predistortion model are repeated until the loss function is minimized, and the trained PDTRANS predistortion model matched with the power amplifier is obtained; and performing pre-distortion compensation on the power amplifier based on the trained PDTRANS pre-distortion model. According to the invention, accurate pre-distortion modeling of the power amplifier is realized.

The invention relates to the technical field of qec correction of digital arrays, in particular to a feedback-based digital qec correction method for a digital array, and the method comprises the following steps: S1, constructing a transceiving channel distortion model, and calculating distortion model parameters; s2, constructing a transmitting terminal pre-distortion model according to the distortion model parameters, and performing transmitting terminal qec correction; and S3, constructing a post-distortion model of the receiving end according to the distortion model parameters, and performing qec correction of the receiving end. According to the scheme, the problem of mirror image and direct current correction of the receiving and transmitting end of the digital array antenna is solved digitally, the method does not depend on hardware design and does not need support of an external reference source, mirror image qec correction is carried out by using a digital method based on feedback, error correction of the mirror image and the local oscillator is also realized by the method, and the method is high in precision and good in portability.

Digital pre-distorter (DPD) coefficients can be used to compensate for non-linearity of a power amplifier (PA). A system can receive a defined waveform from transmit hardware. The system can transmit an output waveform with a defined modulation from the PA. The system can capture samples of the output waveform. The system can submit the samples to a processing system temporarily connected to a transmitter system. The system can compute a PA model using the defined waveform and the samples. The system can determine a plurality of Digital Pre-Distorter (DPD) coefficients for a plurality of power levels, frequencies, and temperatures based on the PA model. The system can store the plurality of DPD coefficients to a memory of the transmitter system. Additionally, the system can add predistortions using the plurality of DPD coefficients to a plurality of input waveforms to correct for impairments introduced by the PA.

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.

The present application relates to a signal processing apparatus, comprising: a first switch unit configured to receive a first analog signal; a first analog-to-digital conversion unit coupled to the first switch unit and configured to convert the first analog signal into a first digital signal; a core processing unit coupled to the first analog-to-digital conversion unit and configured to process the first digital signal and output a second digital signal at least comprising digital pre-distortion information; a first digital-to-analog conversion unit coupled to the core processing unit and configured to convert the second digital signal into a second analog signal; and the second switch unit is coupled to the first digital-to-analog conversion unit and is configured to output the second analog signal. The invention further relates to a signal processing method and electronic equipment. According to the invention, the problems of performance and linearity caused by a power amplifier can be overcome, and the processing performance and the adaptability are relatively high.

A bias circuit (3300) for a power amplifier (3310) is disclosed. The bias circuit (3300) may select between different power sources based on a power need for the power amplifier (3310). As voltage levels between the different power sources may differ at the moment of transition, additional circuitry is provided to smooth the transition between the differing power levels. Further, the bias circuit (3300) may provide bias signals to multiple stacked transistors in the power amplifier (3310) in such a manner so as to avoid collapsing any of the transistors. One such approach is a piecewise linear bias signal. Still further, the bias circuit (3300) may interoperate with predistortion circuitry to assist in linear operation of the power amplifier (3310). Still further, the bias circuit (3300) may interoperate with protection circuitry to prevent over current, over voltage, or over power conditions that may damage the power amplifier (3310).

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.

The invention relates to the technical field of transmit-receive converters, in particular to a short wave transceiver common antenna transmit-receive converter based on a PIN diode. The transmit-receive converter comprises a power control module used for monitoring the output power of a power amplifier in real time and dynamically adjusting the output power through a variable attenuator; the cooperative control unit is configured to adjust the attenuation amount of the output power according to the power control module; determining an adjustment strategy of a pre-distortion coefficient in a digital pre-distortion algorithm; and the digital pre-distortion module is used for determining a pre-distortion coefficient in a digital pre-distortion algorithm according to the adjusted output power and the integer strategy so as to compensate nonlinear distortion of the power amplifier through the pre-distortion coefficient.

This disclosure provides a communication system comprising a first branch and a second branch. The first branch includes a transmit chain and a reference chain. The transmit chain includes a DPD, a DAC, a frequency mixer, a power amplifier (PA), a circulator, a filter, and a first antenna array that are sequentially connected. The second branch includes a receive chain comprising a second antenna array, a low noise amplifier, a frequency mixer, and an ADC that are sequentially connected. In an SBFD slot, the transmit chain is configured to perform downlink radio frequency transmission on a baseband signal; the receive chain is configured to perform uplink radio frequency transmission on a radio signal; and the reference chain collects a radio frequency signal output by the PA, uses the radio frequency signal as a reference signal, and performs linear cancellation processing on a received signal output by the receive chain.

The invention discloses a system for simultaneously suppressing second-order nonlinearity and third-order nonlinearity in a direct modulation laser (DML), which belongs to the field of optical communication, and can simultaneously suppress the second-order nonlinearity and the third-order nonlinearity in the system under the condition of DSP-FREE through the combined action of a broadband pre-distortion circuit and an optical path push-pull structure. Wherein at a transmitting end, a set of Schottky diodes and Chebyshev gradient transmission lines which are connected in parallel reversely are adopted to build a DC-10GHz broadband pre-distortion module, and a radio frequency signal generates a reverse third-order intermodulation (IMD3) component through an analog pre-distortion circuit so as to counteract forward third-order nonlinearity of a laser; at a receiving end, a second-order intermodulation (IMD2) component is differentially eliminated through an optical path push-pull modulation architecture. Compared with a traditional DSP scheme, digital signal processing is not needed, the method has the advantages of being low in complexity and wide in bandwidth, and nonlinear accurate compensation of an optical communication system can be achieved.

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.

Amplitude and phase error correction in a transceiver circuit is provided. In embodiments disclosed herein, a transceiver circuit is configured to equalize an input vector to thereby correct amplitude-amplitude (AM-AM) and amplitude-phase (AM-PM) errors across a modulation bandwidth of the wireless communication circuit. Unlike conventional methods where complicated memory digital predistortion (mDPD) coefficients must be defined and calibrated for each modulation frequency within the modulation bandwidth, the transceiver circuit is configured herein to eliminate modulation frequency dependency of the AM-AM and AM-PM errors. As a result, it is possible to correct the AM-AM and AM-PM errors across the modulation bandwidth with reduced complexity to thereby improve efficiency and linearity of the wireless communication circuit.

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.

A signal predistortion circuit configuration includes a digital predistortion (DPD) circuit, a first transceiver, and a second transceiver, and can reduce the influence of poor signal path insulation when performing a DPD training. During the DPD training, the DPD circuit transmits a training signal through a first signal path to adjust first predistortion parameters, and transmits a training signal through a second signal path to adjust second predistortion parameters. The first signal path includes: a transmitting circuit and an analog-front-end circuit of the first transceiver, a receiving analog circuit and a switch circuit of the second transceiver, and a switch circuit and an analog-to-digital converter (ADC) of the first transceiver. The second signal path includes: a transmitting circuit and an analog-front-end circuit of the second transceiver, a receiving analog circuit and the switch circuit of the first transceiver, and the switch circuit and an ADC of the second transceiver.

The present disclosure provides a system and a method for linearization of a power amplifier chain. The system determines a predistorted signal associated with a coupled power output of a power amplifier along a first transmission path among one or more transmission paths based on a RF input signal received by the transceiver. The system determines, an output signal associated with the coupled power output of the PA along a second transmission path among the one or more transmission paths, where the coupled power output is based on the predistorted signal. The system monitors, the output signal associated with the PA. The system varies the predistorted signal to generate the power output through the PA.

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 invention provides a digital pre-distortion circuit, which comprises a first coupling line structure used for coupling output ends of a plurality of sub-transmitting channels of an antenna circuit; each sub-transmitting channel is used for generating an output radio frequency signal at the output end of the sub-transmitting channel according to an input digital signal; and the processing module is connected with the first coupling line structure and is used for performing pre-distortion according to a signal from the first coupling line structure. The invention further provides an antenna device.

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 disclosure relates to a 5G or 6G communication system for supporting a higher data transmission rate. Disclosed herein are method for a subset of parameters (Ps) from total parameters (Pt) for a Pt based digital pre-distorter (DPD). Initially, corresponding values of the Pt parameters are estimated, at a first time slot of first TIP slots. Further, the Pt parameters are sortec based on contribution of each of the Pt parameter to a first DPD output for the first time slot. Furthermore, the Ps parameters are determined by eliminating parameters with contribution lower than a predetermined threshold from the sorted Pt parameters in order that corresponding DPD outputs for the remaining slots of the first TIP slots are determined using corresponding values of the Ps parameters.

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.