22results about "Phase feedback adaptive predistortion" patented technology

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.

A radio frequency circuit, a method of operating a radio frequency circuit, and an electronic device are provided, the radio frequency circuit including: a multi-tone generation circuit configured to generate a multi-tone signal including a plurality of tones; a pre-distortion circuit configured to pre-distort the multi-tone signal or the modulated signal and output a pre-distorted signal; a power amplifier configured to amplify the pre-distorted signal and output an output signal; and a pre-distortion modeling circuit configured to model a pre-distortion model corresponding to the pre-distortion circuit based on a pre-distortion signal corresponding to the multi-tone signal and the output signal.

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.

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.

Apparatus and methods for biasing power amplifiers are provided herein. In certain embodiments, a power amplifier includes a bipolar transistor having a base biased by a bias network having a reactance that controls an impedance at the transistor base to achieve substantially flat phase response over large dynamic power levels. For example, the bias network can have a frequency response, such as a high-pass or band-pass response, that reduces the impact of power level on phase distortion (AM / PM).

An adaptive digital pre-distortion device includes a legacy digital pre-distortion (DPD) device, one or more processors including processing circuitry, and a memory storing instructions. The instructions, when executed by the one or more processors individually or collectively, cause the adaptive DPD device to receive a plurality of system parameters, estimate, using a neural network, one or more coefficients of the legacy DPD device, and apply the one or more coefficients to the legacy DPD device. The neural network is configured to generate, as outputs, the one or more coefficients based on the plurality of system parameters.

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.

An auto-tuning controller for improving a performance of a power amplifier system is provided. The controller includes an interface including input terminals and output terminals, the interface being configured to acquire input signal conditions of power amplifiers (PAs), a training circuit including a processor and a memory running and storing a Digital Doherty amplifier (DDA) controller (module), a DPD controller (module) and a DDA-DPD neural network (NN). The training circuit is configured to perform sampling the input signal conditions, and selecting a DPD model from a set of polynomial models for the DPD controller and a set of DDA optimization variables for the DDA controller, using optimized DPD model and DDA coefficients, wherein the optimized DPD model and DDA coefficients are provided by performing an offline optimization for the DPD model and DDA coefficients based on a predetermined optimization method, collecting the optimized DPD coefficients and optimized DDA optimization variables, generating online-DDA optimal coefficients and DPD optimal coefficients using a trained DDA-DPD NN, and updating the generated optimal DDA and DPD coefficients via the output terminals of the interface.

An adaptive digital pre-distortion device includes a legacy digital pre-distortion (DPD) device, one or more processors including processing circuitry, and a memory storing instructions. The instructions, when executed by the one or more processors individually or collectively, cause the adaptive DPD device to receive a plurality of system parameters, estimate, using a neural network, one or more coefficients of the legacy DPD device, and apply the one or more coefficients to the legacy DPD device. The neural network is configured to generate, as outputs, the one or more coefficients based on the plurality of system parameters.

A radio-frequency (RF) circuit (100) including: a multi-tone generation circuit configured to generate a multi-tone signal (MT_S) including a plurality of tones; a predistortion circuit (130) configured to predistort the multi-tone signal (MT_S) or a modulation signal (M_S) and output a predistortion signal (PD_S); a power amplifier (140) configured to amplify the predistortion signal (PD_S) and output an output signal (OUT); and a predistortion modeling circuit (150) configured to model a predistortion model corresponding to the predistortion circuit (130) based on the predistortion signal (PD_S) corresponding to the multi-tone signal (MT_S) and the output signal (OUT).

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.

In some embodiments, a power amplifier circuit can include a power amplifier having an input node and an output node, and a load modulation circuit coupled to the output node of the power amplifier. The power amplifier circuit can further include a control profile configured to provide information for generating a control signal for the load modulation circuit, and a control circuit configured to generate and provide the control signal to the load modulation circuit based on the control profile. In some embodiments, the control profile can be further configured to provide information for generating a control signal for a phase compensation circuit.

An amplifier circuit is provided, comprising an amplifier, a feedback path, and an amplifier linearity enhancement circuit. The amplifier has a signal input and a signal output and is configured to generate an amplified signal at the signal output. The feedback path is coupled between the signal output and the signal input, and the amplifier linearity enhancement circuit is located in the feedback path. The amplifier linearity enhancement circuit includes a nonlinear current generator and a phase shift circuit. The nonlinear current generator is configured to provide a nonlinear current based on the amplified signal, and the phase shift circuit is configured to adjust the phase of the nonlinear current to reduce intermodulation distortion of the amplified signal.

An amplifier device (10) comprises a signal input (11) configured to receive an analog signal, a signal output (12) and a main signal path (13) between the signal input and the signal output. Amplifier circuitry (14) is arranged in the main signal path. The amplifier device further comprises signal predistortion circuitry (15). The signal predistortion circuitry comprises analog predistortion circuitry (151) configured to generate a first predistortion signal and digital predistortion circuitry (152) 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 (151) and the digital predistortion circuitry (152) are arranged in parallel signal paths.

A radio-frequency (RF) circuit (100) including: a multi-tone generation circuit configured to generate a multi-tone signal (MT_S) including a plurality of tones; a predistortion circuit (130) configured to predistort the multi-tone signal (MT_S) or a modulation signal (M_S) and output a predistortion signal (PD_S); a power amplifier (140) configured to amplify the predistortion signal (PD_S) and output an output signal (OUT); and a predistortion modeling circuit (150) configured to model a predistortion model corresponding to the predistortion circuit (130) based on the predistortion signal (PD_S) corresponding to the multi-tone signal (MT_S) and the output signal (OUT).

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.

The present disclosure relates to configurable nonlinear filters for digital predistortion. Some embodiments herein describe a radio frequency communication system that may include a transmitter that outputs a radio frequency (RF) transmit signal, the transmitter including a digital predistortion system (DPD) that predistorts the RF transmit signal. The DPD system may include a configurable nonlinear filter having multiple rows, such as a Laguerre filter, wherein at least one row operates with a configurable decimation ratio. The DPD system may also include a decimation filter and a cross switch coupled between the decimation filters.

Disclosed is an electronic device, which includes a predistorter that predistorts an input signal based on a predistortion coefficient to generate a predistortion signal; a power amplifier that amplifies the predistortion signal to generate an output signal; an error correction unit that updates the predistortion coefficient to minimize an Normalized Mean Square Error (NMSE) between the input signal and the output signal; and an ACLR adjustment unit that operates when the NMSE is minimized, calculates an Adjacent Channel Leakage Ratio (ACLR) from the output signal, and updates the predistortion coefficient to minimize a cost function defined based on the ACLR.

An adaptive digital pre-distortion apparatus, an electronic apparatus, and an operation method of the electronic apparatus are provided. The adaptive digital pre-distortion device comprises: a legacy digital pre-distortion (DPD) device; one or more processors including processing circuitry; and a memory storing instructions. The instructions, when executed individually or collectively by the one or more processors, cause the adaptive DPD device to: receive a plurality of system parameters; estimating one or more coefficients of the legacy DPD device using a neural network; and applying the one or more coefficients to the legacy DPD device. The neural network is configured to generate the one or more coefficients as an output based on the plurality of system parameters.

Example embodiments relate to machine learning based digital pre-distortion for power amplifiers. A device may amplify a signal with a power amplifier and transmit the signal. The signal may be received by an internal feedback receiver of the device. The device may further comprise a first machine learning model configured to emulate an external feedback receiver and to generate an emulated feedback signal based on the internal feedback signal. The device may further comprise a second machine learning model configured to determine digital pre-distortion parameters for the power amplifier based on the emulated feedback signal. Apparatuses, methods, and computer programs are disclosed.

Apparatuses and methods for biasing a power amplifier are provided herein. In certain embodiments, a power amplifier includes a bipolar transistor having a base biased by a bias network having a reactance that controls the impedance at the base of the transistor to achieve a substantially flat phase response over a large dynamic power level. For example, the bias network can have a frequency response, such as a high pass or band pass response, that reduces the effect of power level on phase distortion (AM / PM).