85results about "Lookup table adaptive predistortion" patented technology

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.

Certain aspects of the present disclosure provide techniques for pre-distortion training feedback via inductive coupling. An example apparatus includes a receive path; a transmit path comprising an amplifier having a first output that is inductively coupled to the receive path; a memory; and a processor coupled to the memory. The processor is configured to cause the apparatus to obtain a first signal, based on a second signal output by the amplifier, via the receive path being inductively coupled to the first output of the amplifier; determine a parameter for pre-distortion associated with the amplifier based at least in part on the first signal; pre-distort a third signal based at least in part on the parameter; amplify the pre-distorted third signal via the amplifier; and transmit the amplified third signal.

Systems and techniques are provided for power amplifier gain error compensation for a Digital Power Amplifier (DPA). In some aspects, a compensation method includes obtaining in-phase (I) and quadrature-phase (Q) components of a baseband sample corresponding to in-phase input amplitude codes and quadrature-phase input amplitude codes. The in-phase input amplitude codes can be distorted based on first gain pre-compensation information corresponding to an in-phase signal branch of the DPA, to generate pre-distorted output amplitude codes of the I component. The quadrature-phase input amplitude codes can be distorted based on second gain pre-compensation information corresponding to a quadrature-phase signal branch of the DPA, to generate pre-distorted output amplitude codes of the Q component. The DPA can be driven using the pre-distorted output amplitude codes of the I and Q components to generate a Radio Frequency (RF) output.

Techniques are described for implementing multiband digital predistortion in a broadband transmitter in a manner that provides effective compensation of non-linear distortion arising from integration of a high-power amplifier (HPA). Embodiments segment the signal spectrum of a transmit signal into multiple sub-band signals and apply non-linear distortion compensation separately and concurrently for each sub-band signal. The resulting multi-band digital predistortion (mDPD) compensates both for in-band distortion and for distortions from non-linear interactions between the frequency sub-bands. The disclosed mDPD can provide enhanced performance features, such as handling of memory effects, reduced sampling rate requirements for DPD components, and minimizing detrimental spectral regrowth at the HPA output.

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.

Systems and techniques are provided for power amplifier gain error compensation for a Digital Power Amplifier (DPA). In some aspects, a compensation method includes obtaining in-phase (I) and quadrature-phase (Q) components of a baseband sample corresponding to in-phase input amplitude codes and quadrature-phase input amplitude codes. The in-phase input amplitude codes can be distorted based on first gain pre-compensation information corresponding to an in-phase signal branch of the DPA, to generate pre-distorted output amplitude codes of the I component. The quadrature-phase input amplitude codes can be distorted based on second gain pre-compensation information corresponding to a quadrature-phase signal branch of the DPA, to generate pre-distorted output amplitude codes of the Q component. The DPA can be driven using the pre-distorted output amplitude codes of the I and Q components to generate a Radio Frequency (RF) output.

Techniques are described for implementing multiband digital predistortion in a broadband transmitter in a manner that provides effective compensation of non-linear distortion arising from integration of a high-power amplifier (HPA). Embodiments segment the signal spectrum of a transmit signal into multiple sub-band signals and apply non-linear distortion compensation separately and concurrently for each sub-band signal. The resulting multi-band digital predistortion (mDPD) compensates both for in-band distortion and for distortions from non-linear interactions between the frequency sub-bands. The disclosed mDPD can provide enhanced performance features, such as handling of memory effects, reduced sampling rate requirements for DPD components, and minimizing detrimental spectral regrowth at the HPA output.

Systems and methods for front-end linearization using information from a baseband circuit are disclosed. In one aspect, a baseband circuit provides information to a front-end module that uses the information to adjust operating parameter settings such as how an analog predistortion (APD) circuit or power management integrated circuit behaves to provide more linear operation of the front-end module across the frequencies of interest. In exemplary aspects, the front-end module may receive raw information from which the front-end module determines what changes should be made. In alternate exemplary aspects, the baseband circuit provides instructions or coefficients that are then used by the front-end module to make the changes. In either event, the front-end module may optimize operation to reduce power consumption and provide more linear operation so that the transceiver may better operate within the parameters of a given wireless protocol.

A distortion compensation device (2) includes: an amplification target signal acquiring unit (21) that acquires an amplification target signal to which power amplification by a power amplifier (4) is performed; and an operation status signal acquiring unit (22) that acquires an operation status signal indicating an operation status of the power amplifier (4). In addition, the distortion compensation device (2) includes a distortion compensation unit (25) that estimates a signal in which distortion is added to the amplification target signal acquired by the amplification target signal acquiring unit (21) as a predistortion signal for compensating distortion generated in the amplification target signal after power amplification by the power amplifier (4) on the basis of the amplification target signal acquired by the amplification target signal acquiring unit (21) and the operation status signal acquired by the operation status signal acquiring unit (22), and outputs the predistortion signal to the power amplifier (4).

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

A linearization method for a power amplifier includes the following steps. An input signal and an error associated with the input signal are received. Fuzzy statistics is performed on the input signal and the error. A compensation value is calculated according to a fuzzy control table and a defuzzification equation. The compensation value is combined with the input signal to obtain an intermediate signal, and the intermediate signal is input into a power amplifier, so that the power amplifier outputs a first output signal. The first output signal from the power amplifier is fed back into an inverse model of an ideal power amplifier, so that the inverse model outputs a second output signal. A subtraction between the intermediate signal and the second output signal is calculated to obtain the error.

A digital pre-distortion circuit and technique for a signal being amplified. Digital pre-distortion is performed using a model-based pre-distortion function. Pre-distortion is further corrected using a data-driven pre-distortion function. The model-based pre-distortion function and the data-driven pre-distortion function are trained using training data including a digital loopback signal generated by sampling a loopback signal of an amplifier, the digital pre-distorted signal input to the amplifier for a time period, and an intermediate signal output from the model-based pre-distortion function driven by the digital loopback signal or an output of the data-driven pre-distortion function. Parameters may be continually updated in order to account for changes in characteristics of the amplifier.

The present disclosure pertains to a power amplifier system that promotes enhanced signal linearity and overall system efficiency. The system includes a power amplifier with an amplification path for a radio frequency (RF) signal, and detector circuitry operationally linked to sample locations along this path. The detector circuitry captures and transmits signal characteristics of the RF signal. A voltage standing wave ratio (VSWR) quadrant data generator in communication with the detector circuitry generates VSWR quadrant data based on the detected signal characteristics. The baseband circuitry, comprised of a memory unit preconfigured with digital pre-distortion (DPD) coefficients and a DPD processor, controls the shaping of pre-distortion applied to the RF signal based on the VSWR data, thereby enhancing signal linearity. The components of the system interconnect and collaboratively function to optimize the performance and efficiency of the power amplifier system.

This electronic device may comprise: 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. When executed by the at least one processor, the instructions can cause the electronic device to: predistort, on the basis of the first DPD path, a first digital signal having a first sampling rate; transmit a first output signal generated on the basis of the power amplifier from the predistorted first digital signal; provide, to the DPD circuit, on the basis of a correlation value for the first digital signal and the first output signal, a control signal for activating the second DPD path; predistort, on the basis of the second DPD path, a second digital signal having a second sampling rate; and transmit a second output signal generated on the basis of the power amplifier from the predistorted second digital signal.

Methods and devices are provided in which a processor of a user equipment (UE) combines loop-back signals from a plurality of antenna paths of the UE to generate a combined signal. The loop-back signals are based on a signal transmitted over the antenna paths. The processor determines power amplifier (PA) polynomials based on a comparison of the combined signal to the signal transmitted over the antenna paths. The processor generates a single look-up table (LUT) for the PA polynomials. The processor applies the single LUT to a transmitted signal of the UE to compensate for PA non-linearity.

An apparatus for controlling the gain and phase of an input signal input to a power amplifier comprises a gain control loop configured to control the gain of the input signal based on power levels of the input signal and an amplified signal output by the power amplifier, to obtain a predetermined gain of the amplified signal, and a phase control loop configured to obtain an error signal related to a phase difference between a first signal derived from the input and a second signal derived from the amplified signal, and control the phase based on the error signal, to obtain a predetermined phase of the amplified signal. The phase control loop is arranged to delay the first signal before obtaining the error signal, such that the delayed first signal and the second signal used to obtain the error signal correspond to the same part of the input signal. The gain control loop may compare a power of a third signal derived from the input signal and a power of a fourth signal derived from the amplified signal. The third and fourth signals may be output by first and second couplers, which may have coupling factors that are selected such that the third and fourth signals have the same power level when the amplified signal has the predetermined gain. The current gain and phase of the amplified signal may be dependent on an operational history of the power amplifier, which may be a GaN power amplifier, and the apparatus and power amplifier may be included in a satellite. In another embodiment, a satellite includes a power amplifier control system that uses a feed-forward control loop to control both the gain and phase of a signal input to the power amplifier.

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.

A power amplifier and a method of controlling a power amplifier are described. The power amplifier (300) comprises a hybrid combiner (310) comprising a first input port and a second input port, an isolated port and an output port, wherein the hybrid combiner (310) delivers an output power at the output port. A balanced amplifier arrangement (320) is comprised, the balanced amplifier arrangement (320) comprising a main amplifier arrangement, a first peaking amplifier and a second peaking amplifier, wherein the output of the main amplifier arrangement and the outputs of the first and second peaking amplifiers are coupled to the first and second input ports of the hybrid combiner (310) to provide the output power at the output port. A third peaking amplifier (330) has an output coupled to the isolated port of the hybrid combiner (310). A peaking signal distribution circuit distributes a peaking amplification signal to the input ports of the first, second and third peaking amplifiers.

The present disclosure provides a compensation circuit module, a power amplifier component, a compensation method and an apparatus. The compensation circuit module includes at least: a variable resistor, a detection component and a control component; the detection end of the detection component is connected to the DC blocking capacitor of the power amplifier for detecting the voltage swing of the input signal of the DC blocking capacitor; the control component is connected to the detection component for outputting a control signal according to the input signal detected by the detection component; the variable resistor is connected to the output end of the control component for changing the resistance connected to the power amplifier according to the control signal, and the resistance of the variable resistor connected to the power amplifier is used to constitute the feedback resistance of the power amplifier; the feedback resistance is used to increase when the gain of the power amplifier decreases; the increased feedback resistance is used to keep the gain in the flat section of the gain change curve; the resistance of the variable resistor can be adjusted by the input signal to achieve compensation for the gain of the power amplifier and maintain the linearity of the input and output of the power amplifier.

A predistortion circuit for a wireless transmitter includes a signal input configured to receive a baseband signal. Further, the predistortion circuit includes a predistorter configured to generate a predistorted baseband signal using the baseband signal and a select of one of a first predistorter configuration and a second predistorter configuration.

A digital predistortion module (DPD) (300) for linearization of a non-linear electronic device is disclosed. The DPD module (300) comprises an input module (310) configured to receive an input signal x(n) and a function module (320) defined by a pruned Volterra series with memory polynomial terms, wherein the function module comprises a set of basis function components Fj (p ( j ) 1, q ( j ) 1 p2'> > q2 (i) I A ( i ), D ( j ) 1, Di'> > Ds >, D ( j ) 4, x(n)). The polynomial order and time delay of the function module (320) are determined or calculated by algorithm based on the input signal x(n), and an error signal e(n) representing a difference between the input signal x(n) and an output signal z(n) of the non-linear electronic device. The DPD module (300) further comprises an output module (330) configured to combine outputs from the set of basic function components to output an output signal y(n).

Example embodiments relate to machine learning based power amplifier digital predistortion. A device can utilize a power amplifier to amplify and transmit a signal. The signal can be received by an internal feedback receiver of the device. The device can further include a first machine learning model configured to emulate an external feedback receiver and generate an emulated feedback signal based on the internal feedback signal. The device can further include a second machine learning model configured to determine a digital predistortion parameter for the power amplifier based on the emulated feedback signal. Apparatuses, methods, and computer programs are disclosed.

A method, apparatus and computer readable storage medium for power amplifier linearization are disclosed. In a method, a plurality of parameters is determined for a predistortion process of the at least one power amplifier to reduce a difference between a reference signal and a feedback signal and to enhance efficiency of the at least one power amplifier. The predistortion process is caused to be performed using at least the plurality of parameters to linearize the at least one power amplifier.

Systems and methods for front-end linearization using information from a baseband circuit are disclosed. In one aspect, a baseband circuit provides information to a front-end module that uses the information to adjust operating parameter settings such as how an analog predistortion (APD) circuit or power management integrated circuit behaves to provide more linear operation of the front-end module across the frequencies of interest. In exemplary aspects, the front-end module may receive raw information from which the front-end module determines what changes should be made. In alternate exemplary aspects, the baseband circuit provides instructions or coefficients that are then used by the front-end module to make the changes. In either event, the front-end module may optimize operation to reduce power consumption and provide more linear operation so that the transceiver may better operate within the parameters of a given wireless protocol.

Systems, devices, and methods are provided for using model architecture search for hardware configurations. The method includes receiving, by a computer-implemented system, information associated with a pool of processing units, receiving, by the computer-implemented system, a dataset associated with a data transformation operation, training a parameterized model associated with the data transformation operation based on the dataset and the information associated with the pool of processing units, where the training includes updating at least one parameter of the parameterized model associated with configuring at least a subset of the processing units in the pool, and outputting one or more configurations for at least a subset of the processing units in the pool based on the training.

There is provided mechanisms for operating a digital pre-distorter for a non-linear electronic device. A method comprises receiving an input signal destined to be input to the non-linear electronic device. The method comprises selecting, for basis functions that represent input-output characteristics of the non-linear electronic device, a set of tap delays. The set of tap delays is selected using a block orthogonal matching pursuit algorithm. The method comprises obtaining an output signal by subjecting the input signal to a linearization function defined by the basis functions with the selected set of tap delays. The method comprises providing the output signal as input to the non-linear electronic device.

An amplifier device may include a signal input configured to receive an analog signal, a signal output, and a main signal path between the signal input and the signal output. Amplifier circuitry is arranged in the main signal path. The amplifier device has signal predistortion circuitry including analog predistortion circuitry configured to generate a first predistortion signal and digital predistortion circuitry configured to generate a second predistortion signal. The signal predistortion circuitry is configured to adapt a signal in the main signal path based on the first predistortion signal and on the second predistortion signal for at least partially compensating a non-linearity of the amplifier circuitry. The analog predistortion circuitry and the digital predistortion circuitry are arranged in parallel signal paths.

A power amplifier with analog predistortion is disclosed. In one aspect, a signal in the transmission chain is sampled to determine if a phase distortion (delay or advancement) is present. Information about the sampled signal is provided to a control circuit, which uses an analog predistortion circuit to inject a correction signal into the transmission chain so as to offset or compensate for the phase distortion. In an exemplary aspect, the analog predistortion circuit may use a variable capacitor to generate the correction signal that is injected. This detection and adjustment may be done in the front end of the transmission chain so as to avoid reliance on a baseband processor. Use of such analog predistortion helps maintain desired linear operation over the large bandwidths of emerging wireless communication standards.

Aspects of the present disclosure provide signal amplification. An example method generally includes amplifying a version of a first input signal with a power amplifier in a first state where a bias voltage of the power amplifier is set to a first voltage based on a first tracking mode; obtaining a first output signal of the power amplifier in a second state where the bias voltage is set to a second voltage less than the first voltage; determining a predistortion associated with the power amplifier based at least in part on the obtained first output signal; applying the predistortion to the first input signal; and amplifying a version of the predistorted first input signal with the power amplifier in a third state where the bias voltage is set to a third voltage based on a second tracking mode, wherein the third voltage is less than the first voltage.

The present disclosure is a novel utility of a software defined radio (SDR) based Distributed Antenna System (DAS) that is field reconfigurable and support multi-modulation schemes (modulation-independent), multi-carriers, multi-frequency bands and multi-channels. The present disclosure enables a high degree of flexibility to manage, control, enhance, facilitate the usage and performance of a distributed wireless network such as flexible simulcast, automatic traffic load-balancing, network and radio resource optimization, network calibration, autonomous / assisted commissioning, carrier pooling, automatic frequency selection, frequency carrier placement, traffic monitoring, traffic tagging, pilot beacon, etc.