WO2022183834A1

WO2022183834A1 - Radio frequency circuit and pre-distortion compensation method and apparatus therefor, and electronic device

Info

Publication number: WO2022183834A1
Application number: PCT/CN2021/143596
Authority: WO
Inventors: 林颢; 李俊强; 刘鑫
Original assignee: 展讯通信（上海）有限公司
Priority date: 2021-03-03
Filing date: 2021-12-31
Publication date: 2022-09-09
Also published as: CN113014207B; CN113014207A

Abstract

Provided in the present application are a radio frequency circuit and a pre-distortion compensation method and apparatus therefor, and an electronic device. The method comprises: determining a target output power of a radio frequency circuit; according to a pre-stored first power and a first compensation parameter corresponding to the first power, determining a second compensation parameter corresponding to the target output power and a gain adjustment amount; configuring the second compensation parameter for a pre-distorter in a radio frequency circuit, and performing gain adjustment on the radio frequency circuit according to the gain adjustment amount, such that the output power of the radio frequency circuit reaches the target output power. There is no need to keep parameters corresponding to all power levels, and only a compensation parameter corresponding to one power level needs to be determined again when an operating environment changes, such that the calculation amount can be reduced, training signals can be prevented from being frequently transmitted into the air, so as to reduce interference to other devices, and the memory occupation amount can also be reduced.

Description

Radio frequency circuit and its predistortion compensation method, device and electronic equipment

This application claims the priority of the Chinese patent application with the application number 202110236931.1 and the application title "Radio Frequency Circuit and its Predistortion Compensation Method, Device and Electronic Equipment" filed with the China Patent Office on March 3, 2021, the entire content of which is approved by Reference is incorporated in this application.

technical field

The present application relates to the technical field of radio frequency circuits, and in particular, to a radio frequency circuit and a predistortion compensation method, apparatus and electronic device thereof.

Background technique

With the development of wireless communication technology and the continuous increase of signal transmission rate, methods of higher modulation rate are widely used in wireless communication technology, such as Orthogonal Frequency Division Multiplexing, 256QAM (Quadrature Amplitude Modulation, Quadrature Amplitude Modulation), etc. , with the constant increase of the peak-to-average ratio of the signal, in order to ensure the correct transmission of the data, a higher requirement is placed on the linearity of the radio frequency device.

In a radio frequency circuit, a power amplifier (Power Amplitfier, PA) is an important source of nonlinearity, and the existing technology mainly uses a digital pre-distortion (Digital Pre-Distortion, DPD) technology to compensate for the nonlinearity of the power amplifier.

However, since the distortion characteristics of the power amplifier are different under different output power levels, in order to ensure that the output signal performance of each power level meets the requirements, the prior art needs to save the pre-distortion compensation coefficient corresponding to each power level, which requires It takes a lot of time to perform data calculation, and it takes up a lot of memory to save the data.

SUMMARY OF THE INVENTION

The present application provides a radio frequency circuit and a predistortion compensation method, device and electronic device thereof, so as to solve the problems existing in the prior art.

In a first aspect, the present application provides a predistortion compensation method for a radio frequency circuit, including:

Determine the target output power of the RF circuit;

Determine the second compensation parameter and the gain adjustment amount corresponding to the target output power according to the pre-stored first power and the first compensation parameter corresponding to the first power, wherein the first compensation parameter is the radio frequency circuit When the output power is the corresponding predistortion compensation parameter of the first power, the first power is any power within the output power range of the radio frequency circuit;

Configuring the second compensation parameter to a predistorter in the radio frequency circuit, and adjusting the gain of the radio frequency circuit according to the gain adjustment amount, so that the output power of the radio frequency circuit reaches the target output power .

In some embodiments, the determining of the second compensation parameter and the gain adjustment amount corresponding to the target output power according to the pre-stored first power and the first compensation parameter corresponding to the first power includes:

Determine the gain adjustment amount according to the difference between the first power and the target output power;

The second compensation parameter is determined according to the gain adjustment amount and the first compensation parameter.

In some embodiments, the determining the second compensation parameter according to the gain adjustment amount and the first compensation parameter includes:

Allocating the gain adjustment amount to obtain an analog gain adjustment amount;

The second compensation parameter is determined according to the analog gain adjustment amount and the first compensation parameter.

In some embodiments, the determining the second compensation parameter according to the analog gain adjustment amount and the first compensation parameter includes:

Calculate the second compensation parameter by the following formula:

w _cq,m = w _{ref q,m} *(g _ca ^(q-1) )

Wherein, w _{c q,m} is the second compensation parameter, w _{ref q,m} is the first compensation parameter, G _ca is the analog gain adjustment amount, g _ca is the linear value of the analog gain adjustment amount, q is the nonlinear order, m for memory depth.

In some embodiments, performing gain adjustment on the radio frequency circuit according to the gain adjustment amount includes:

Allocate the gain adjustment amount to obtain a digital gain adjustment amount and an analog gain adjustment amount;

According to the digital gain adjustment amount, digital gain adjustment is performed on the digitally adjustable gain module in the radio frequency circuit;

According to the analog gain adjustment amount, the analog gain adjustment is performed on the analog adjustable gain module in the radio frequency circuit.

In some embodiments, allocating the gain adjustment amount includes:

The integer part of the gain adjustment amount is assigned as the analog gain adjustment amount, and the fractional part of the gain adjustment amount is assigned as the digital gain adjustment amount.

In some embodiments, it also includes:

When the radio frequency circuit outputs the first power, acquiring the first digital gain of the digital adjustable gain module in the radio frequency circuit, and acquiring the first analog gain of the analog adjustable gain module in the radio frequency circuit;

acquiring a first feedback signal when the radio frequency circuit outputs the first power;

determining the first compensation parameter according to the first digital gain, the first analog gain and the first feedback signal;

The corresponding relationship between the first power and the first compensation parameter is saved.

In a second aspect, the present application provides a predistortion compensation device for a radio frequency circuit, including:

a first determining module, used for determining the target output power of the radio frequency circuit;

A second determination module, configured to determine a second compensation parameter and a gain adjustment amount corresponding to the target output power according to the pre-stored first power and the first compensation parameter corresponding to the first power, wherein the first The compensation parameter is the corresponding predistortion compensation parameter when the output power of the radio frequency circuit is the first power, and the first power is any power within the output power range of the radio frequency circuit;

A processing module configured to configure the second compensation parameter to a predistorter in the radio frequency circuit, and perform gain adjustment on the radio frequency circuit according to the gain adjustment amount, so that the output power of the radio frequency circuit reaches the target output power.

In a third aspect, the present application provides a radio frequency circuit, including: a gain distribution module, a digital adjustable gain module, a predistorter, a predistortion parameter estimation module, an analog adjustable gain module, a power amplifier, and a feedback module;

The digitally adjustable gain module is used to adjust the power of the input signal, and send the obtained first output signal to the predistorter and the predistortion parameter estimation module respectively;

The predistorter is configured to perform predistortion processing on the first output signal, and send the obtained second output signal to the analog adjustable gain module;

The analog adjustable gain module is used to adjust the power of the second output signal, and send the obtained third output signal to the power amplifier;

The power amplifier is configured to perform power amplification on the third output signal, send the obtained fourth output signal to the feedback module, and output the fourth output signal;

The feedback module is configured to generate a feedback signal based on the fourth output signal, and send the feedback signal to the predistortion parameter estimation module;

The predistortion parameter estimation module is configured to determine a compensation parameter of the predistorter according to the first output signal and the feedback signal, and configure the compensation parameter to the predistorter;

The gain distribution module is used for gain distribution to the digital adjustable gain module and the analog adjustable gain module.

In a fourth aspect, the present application provides an electronic device including the above-mentioned radio frequency circuit.

A radio frequency circuit and a predistortion compensation method, device and electronic device thereof provided by the present application, wherein the method includes: determining a target output power of the radio frequency circuit; The second compensation parameter and the gain adjustment amount corresponding to the target output power, wherein the first compensation parameter is the corresponding predistortion compensation parameter when the output power of the radio frequency circuit is the first power, and the first power is within the output power range of the radio frequency circuit. Any power; configure the second compensation parameter to the predistorter in the radio frequency circuit, and adjust the gain of the radio frequency circuit according to the gain adjustment amount, so that the output power of the radio frequency circuit reaches the target output power. In this application, the pre-distortion compensation parameters corresponding to any output power level are pre-stored first, and when signals of other power levels need to be output, the compensation parameters corresponding to other power levels can be calculated according to the pre-stored compensation parameters, thereby , because it is not necessary to maintain the parameters corresponding to all power levels, on the one hand, when the working environment changes, it is only necessary to re-determine the compensation parameters corresponding to one power level, which can reduce the amount of calculation and avoid frequent sending of training signals to the air. Reduce interference to other devices; on the other hand, it can also reduce memory usage.

Description of drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the disclosure and together with the description serve to explain the principles of the disclosure.

Fig. 1 is the working principle diagram of the predistorter;

2 is a schematic structural diagram of a radio frequency circuit provided by an embodiment of the present application;

3 is a schematic diagram of a digital predistortion compensation method provided by an embodiment of the present application;

4 is a schematic diagram of determining and saving a first compensation parameter corresponding to a first power in an embodiment of the present application;

FIG. 5 is a schematic diagram of a predistortion compensation apparatus of a radio frequency circuit according to an embodiment of the present application.

From the foregoing drawings, there have been shown specific embodiments of the present disclosure, which will be described in greater detail hereinafter. These drawings and written descriptions are not intended to limit the scope of the disclosed concepts in any way, but rather to illustrate the disclosed concepts to those skilled in the art by referring to specific embodiments.

Detailed ways

In order to make the purposes, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments These are some embodiments of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. As used in the embodiments of this application, the singular forms "a" and "the" are intended to include the plural forms as well, unless the context clearly dictates otherwise.

It should also be noted that the terms "comprising", "comprising" or any other variation thereof are intended to encompass non-exclusive inclusion, such that a commodity or system comprising a list of elements includes not only those elements, but also includes not explicitly listed other elements, or elements inherent to the commodity or system. Without further limitation, an element defined by the phrase "comprising a..." does not preclude the presence of additional identical elements in the article or system that includes the element.

In RF circuits, power amplifiers are an important source of nonlinearity, and nonlinearity can lead to Error Vector Magnitude (EVM) and Adjacent Channel Leakage Ratio (ACLR), which, as the input signal increases, The output end of the power amplifier gradually enters the compression region, which causes the peak value of the input signal to begin to be compressed, thereby affecting the quality of the output signal of the radio frequency circuit.

In the prior art, in order to ensure the signal quality, one processing method is to use power backoff, so that the input signal works in the linear region of the power amplifier. However, in this case, the efficiency of the power amplifier is very low, which will lead to energy loss. A lot of waste, and unable to transmit high power, resulting in a very small range of its wireless signal coverage.

Another processing method in the prior art is to use digital predistortion technology, that is, before the input signal enters the power amplifier, the input signal is preprocessed in advance, so that the part of the input signal that enters the compression area is processed in advance to supplement the power. nonlinear distortion caused by the amplifier.

Specifically, FIG. 1 is a working principle diagram of the predistorter. As shown in FIG. 1 , since the output power of the power amplifier reaches a certain level, the peak value of the output signal will be compressed, resulting in the compression of the peak power and the distortion of the output signal. The working principle of digital predistortion is to pre-compensate the signal in the compression area. The pre-compensated signal is compressed by the power amplifier, and finally the distortion of the power amplifier output is reduced relative to the original signal, thereby completing the ACLR of the output signal of the power amplifier. and EVM improvements.

The digital predistortion technology uses the transmit signal and the feedback signal of the power amplifier to estimate the parameters of the predistorter, so that the excitation response of the predistorter and the response of the power amplifier are inverse functions of each other in the case of the baseband model. Parameter estimation of the predistorter. Since power amplifiers have different distortion characteristics at different power levels, in order to ensure the quality of output signals at different power levels, output signals at different power levels need to be compensated, and the compensation parameters are different.

A commonly used compensation method at present is to estimate the power in advance based on this power before using a certain power level, and store the predistorter parameters of this power level, so that it is necessary to provide storage for each power level. When the working environment of the device changes, such as the increase of the ambient temperature of the device, the aging of the device, etc., all power levels need to be re-estimated, and calibration signals are frequently sent into the air to complete the traversal of each power level.

The disadvantage of the prior art is that after the working environment changes, all power levels need to be re-estimated. On the one hand, training sequences need to be frequently transmitted into the air, causing interference to other devices, and at the same time occupying the hardware resources of the device for parameter estimation. , increase the power consumption of the device and occupy the processing capacity of the device; on the other hand, the compensation parameters of the predistorter must be stored in the memory for different power allocations, which increases the hardware cost of the device.

The radio frequency circuit and the predistortion compensation method, device and electronic device thereof provided by the present application aim to solve the above technical problems in the prior art.

The main idea of the solution of the present application is as follows: for different output power levels of the radio frequency circuit, the present application proposes a normalized pre-distortion compensation method. First, the corresponding relationship between a certain power level and the compensation parameter is pre-stored, and when other power levels need to be output In the case of signals of different power levels, the compensation parameters of the predistorters corresponding to other power levels are calculated and corrected according to the pre-stored compensation parameters, which can effectively solve the problem of frequently estimating the predistorter parameters corresponding to all power levels. Storing compensation parameters for a power level can reduce memory usage.

The technical solutions of the present application and how the technical solutions of the present application solve the above-mentioned technical problems will be described in detail below with specific examples. The following specific embodiments may be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. The embodiments of the present application will be described below with reference to the accompanying drawings.

First, the application scenario of the solution of the present application is explained.

FIG. 2 is a schematic structural diagram of a radio frequency circuit provided by an embodiment of the present application. The technical solution of the present application can be applied to the radio frequency circuit in FIG. 1. As shown in FIG. 2, the radio frequency circuit includes: a gain distribution module 10, a digitally adjustable gain Module 11 , predistorter 12 , predistortion parameter estimation module 13 , analog adjustable gain module 14 , power amplifier 15 and feedback module 16 .

The radio frequency circuit can be specifically divided into two sub-links, namely the transmission chain and the predistortion estimation chain, wherein the transmission chain includes a digital adjustable gain module 11, a predistorter 12, an analog adjustable gain module 14, and a power amplifier. 15 ; the predistortion estimation link includes a predistortion parameter estimation module 13 and a feedback module 16 .

Referring to FIG. 2 , the digitally adjustable gain module 11 is used to adjust the power of the input signal, and send the obtained first output signal to the predistorter 12 and the predistortion parameter estimation module 13 respectively. Specifically, the input signal may be a digital baseband signal x, and the digital baseband signal x completes power adjustment processing through the digital adjustable gain module 11 to obtain a first output signal xdvga, which is respectively sent to the predistorter 12 and the predistortion parameter estimation module 13 .

The predistorter 12 is configured to perform predistortion processing on the first output signal, and send the obtained second output signal to the analog adjustable gain module 14 . The first output signal xdvga is modified by the predistorter 12 to cancel the distortion of the power amplifier 15 to obtain the second output signal y, which is sent to the analog adjustable gain module 14 .

Optionally, a digital-to-analog converter 17 and an up-converter 18 are arranged between the predistorter 12 and the analog adjustable gain module 14 in sequence. The second output signal y is first sent to the digital-to-analog converter 17 for digital-to-analog conversion to obtain an analog baseband signal, which is then transferred to a radio frequency signal by the up-converter 18 , and finally sent to the analog adjustable gain module 14 .

The analog adjustable gain module 14 is used to adjust the power of the second output signal, and send the obtained third output signal to the power amplifier 15 ; After the signal is received, the power of the radio frequency signal is adjusted to obtain a third output signal yavga, which is sent to the power amplifier 15 .

The power amplifier 15 is used for power amplifying the third output signal, sending the obtained fourth output signal to the feedback module 16, and outputting the fourth output signal; specifically, the power amplifier 15 powers the third output signal yavga Amplified, part of the output signal of the power amplifier 15 is transmitted to the antenna for transmission, and the other part is sent to the feedback module 16 through the coupler 22 for parameter estimation of the predistorter 12 .

The feedback module 16 is configured to generate a feedback signal based on the fourth output signal, and send the feedback signal to the predistortion parameter estimation module 13; specifically, after receiving the output signal of the power amplifier 15, the feedback module 16 generates a corresponding feedback signal, for parameter estimation of the predistorter 12 .

Optionally, the feedback module 16 includes an adjustable attenuator 19, a down-converter 20, and an analog-to-digital converter 21. The output of the coupler 22 is adjusted to an appropriate power through the adjustable attenuator 19, and then input to the down-converter 20 to change the power. As an analog baseband signal, the analog baseband signal is converted into a digital feedback signal zfb through an analog-to-digital converter, and then input to the predistortion parameter estimation module 13 .

The predistortion parameter estimation module 13 is configured to determine the compensation parameters of the predistorter 12 according to the first output signal and the feedback signal, and configure the compensation parameters to the predistorter 12; specifically, the predistortion parameter estimation module 13 according to the first output signal The xdvga and the digital feedback signal zfb are modeled to estimate the predistortion compensation parameter which is an inverse function of the power amplifier 15 model, and configure it into the predistorter 12 to take effect immediately.

The gain distribution module 10 is used for gain distribution to the digital adjustable gain module 11 and the analog adjustable gain module 14 . Specifically, the gain distribution module 10 realizes different output powers, assuming that the output power is Pout, the gain of the power amplifier 15 is Gpa, the gain of the analog adjustable gain module 14 is Gavga, the gain of the digital adjustable gain module 11 is Gdvga, and the gain of the baseband The power in the digital domain (that is, the power of the input signal) is Pbb, and the gain from the digital domain to the analog domain is Gdac, then:

Pout=Pbb+Gdac+Gdvga+Gavga+Gpa

Therefore, the gain distribution module 10 can change the output power Pout by adjusting the gain Gdvga of the analog adjustable gain module 14 and the gain Gavga of the digital adjustable gain module 11 , that is, to adjust the output power.

In some embodiments, a predistortion compensation method for a radio frequency circuit is provided. FIG. 3 is a schematic diagram of a digital predistortion compensation method provided by an embodiment of the present application. As shown in FIG. 3 , the method is applied to the radio frequency shown in FIG. 2 . Taking the circuit as an example to explain, the method mainly includes the following steps:

S100. Determine the target output power of the radio frequency circuit;

The target output power refers to the power expected to be output by the radio frequency circuit, and the target output power may be determined according to actual requirements, for example, according to an output task.

S200. Determine a second compensation parameter and a gain adjustment amount corresponding to the target output power according to the pre-stored first power and the first compensation parameter corresponding to the first power, wherein the first compensation parameter is that the output power of the radio frequency circuit is the first The corresponding pre-distortion compensation parameter when the power is used, and the first power is any power within the output power range of the radio frequency circuit;

The first compensation parameter refers to a predistortion compensation parameter configured by a predistorter in the radio frequency circuit when the output power of the radio frequency circuit is the first power, and the first compensation parameter may be predetermined and saved.

In addition, the first power may be any power within the output power range of the radio frequency circuit, for example, may be the maximum output power Pmax or the minimum output power Pmin, or any value between the maximum output power Pmax and the minimum output power Pmin , for example, (Pmax+Pmin)/2.

In this embodiment, according to the pre-stored first power and the first compensation parameter corresponding to the first power, the second compensation parameter and the gain adjustment amount corresponding to the target output power can be determined, and the second compensation parameter is used for the radio frequency circuit. The predistorter is configured with the gain adjustment amount, and the gain adjustment amount is used to adjust the gain of the adjustable gain module in the radio frequency circuit, thereby changing the output power of the radio frequency circuit.

Optionally, when the target output power is the same as the first power, the first compensation parameter may be directly used as the second compensation parameter.

S300. Configure the second compensation parameter to the predistorter in the radio frequency circuit, and adjust the gain of the radio frequency circuit according to the gain adjustment amount, so that the output power of the radio frequency circuit reaches the target output power.

After the second compensation parameter and the gain adjustment amount corresponding to the target output power are determined, the predistortion parameter estimation module in the radio frequency circuit can configure the second compensation parameter to the predistorter in the radio frequency circuit and take effect immediately, and the radio frequency The gain distribution module in the circuit adjusts the gain of the adjustable gain module in the radio frequency circuit according to the gain adjustment amount, so that the output power of the radio frequency circuit reaches the target output power by performing predistortion compensation parameter configuration and gain adjustment.

This embodiment provides a predistortion compensation method for a radio frequency circuit. First, the predistortion compensation parameters corresponding to any output power level are pre-stored, and when signals of other power levels need to be output, the pre-stored compensation parameters can be calculated Compensation parameters corresponding to other power levels need to be determined. Therefore, since there is no need to maintain the parameters corresponding to all power levels, on the one hand, when the working environment changes, only the compensation parameters corresponding to one power level need to be re-determined, which can reduce the amount of calculation, and Frequent sending of training signals to the air can be avoided to reduce interference to other devices; on the other hand, memory usage can also be reduced.

For example, assuming that the training time required to determine the compensation parameters corresponding to one power level is t1, the memory occupancy is m1, and the power level of the output signal of the radio frequency circuit has a total of N gears, then the parameter training required for all gears is completed. The time is t1×N, and the required memory footprint is m1×N, while the time required for this application is only t1, and the memory footprint is only m1, so the convergence of parameters can be quickly completed, the training time can be shortened, and the predistortion can be achieved. The power amplifier can fast track the characteristics of the power amplifier.

In some embodiments, determining the second compensation parameter and the gain adjustment amount corresponding to the target output power according to the pre-stored first power and the first compensation parameter corresponding to the first power, including:

S210. Determine the gain adjustment amount according to the difference between the first power and the target output power;

S220. Determine the second compensation parameter according to the gain adjustment amount and the first compensation parameter.

Specifically, after the target output power is determined, the gain adjustment amount required to adjust the output power to the target output power may be determined according to the pre-stored first power.

For example, assuming that the first power is 20dbm and the target output power is 15dbm, it can be determined that the difference between the first power and the target output power is 5dbm, that is, the gain adjustment amount is 5dbm.

In addition, based on the obtained gain adjustment amount and in combination with the first compensation parameter corresponding to the pre-stored first power, the second compensation parameter that needs to be configured for the predistorter in the radio frequency circuit can be determined, so that the gain adjustment is performed according to the gain adjustment amount. When adjusting and configuring the second compensation parameter to the predistorter in the radio frequency circuit, the output power can reach the target output power.

In some embodiments, the second compensation parameter is determined according to the gain adjustment amount and the first compensation parameter, including:

S221: Allocate the gain adjustment amount to obtain the analog gain adjustment amount;

S222. Determine the second compensation parameter according to the analog gain adjustment amount and the first compensation parameter.

Specifically, according to the specific structure of the radio frequency circuit shown in FIG. 2 , after the first compensation parameter is configured to the predistorter, the output from the digital adjustable gain module xdvga to the digital feedback signal zfb is a linear model. Therefore, adjusting the digital The gain of the adjustable gain module will not affect the digital feedback signal zfb. When adjusting the gain of the analog adjustable gain module, the first compensation parameter will be adapted to other modules in the RF circuit. Therefore, the gain adjustment amount can be adjusted first. distribution to obtain the analog gain adjustment amount, and then determine the second compensation parameter according to the analog gain adjustment amount and the first compensation parameter.

In some embodiments, the second compensation parameter is determined according to the analog gain adjustment amount and the first compensation parameter, including:

Calculate the second compensation parameter by the following formula:

w _{c q,m} =w _{ref q,m} *(g _ca ^(q-1) )

Among them, w _{c q,m} is the second compensation parameter, w _refq,m is the first compensation parameter, G _ca is the analog gain adjustment amount, g _ca is the linear value of the analog gain adjustment amount, q is the nonlinear order, and m is the memory depth.

In some embodiments, the gain adjustment of the radio frequency circuit according to the gain adjustment amount includes:

S310: Allocate the gain adjustment amount to obtain the digital gain adjustment amount and the analog gain adjustment amount;

S320, according to the digital gain adjustment amount, perform digital gain adjustment on the digitally adjustable gain module in the radio frequency circuit;

S330. Perform analog gain adjustment on the analog adjustable gain module in the radio frequency circuit according to the analog gain adjustment amount.

Specifically, the digital adjustable gain module and the analog adjustable gain module in the radio frequency circuit are distributed for performing digital gain adjustment and analog gain adjustment.

Among them, digital gain adjustment is mainly used to adjust the power in the digital domain before the digital-to-analog converter to complete the adjustment of the RF output signal. The power adjustment accuracy of digital gain adjustment is high, but the dynamic range of adjustment is small; analog gain adjustment is mainly used to adjust the power by adjusting The gain after the digital-to-analog converter is used to control the output power. The adjustment dynamic range of the analog gain adjustment is large, but the power adjustment accuracy is low. Therefore, in this embodiment, the digital gain adjustment and the analog gain adjustment are combined. Gain adjustment, so as to ensure a larger adjustment dynamic range, but also to ensure adjustment accuracy.

In some embodiments, allocating the gain adjustment amount includes assigning an integer part of the gain adjustment amount as an analog gain adjustment amount, and assigning a fractional part of the gain adjustment amount as a digital gain adjustment amount.

Specifically, since the power adjustment precision of digital gain adjustment is high, but the dynamic range of adjustment is small, while the adjustment dynamic range of analog gain adjustment is large, but the power adjustment precision is low, therefore, the gain adjustment can be performed by the analog adjustable gain module. The coarse adjustment work is performed by the digital adjustable gain module, and the fine adjustment work of the gain adjustment is performed.

Therefore, the gain adjustment amount can be divided into integer parts and fractional parts, the integer part of the gain adjustment amount can be assigned as the analog gain adjustment amount, and the fractional part of the gain adjustment amount can be assigned as the digital gain adjustment amount. In a combined manner, the gain adjustment can be accurately realized.

For example, assuming that the gain adjustment amount is 2.5dbm, the analog gain adjustment amount can be allocated as 2dbm, and the digital gain adjustment amount is 0.5dbm.

In some embodiments, the step of determining and saving the first compensation parameter corresponding to the first power is further included.

FIG. 4 is a schematic diagram of determining and saving the first compensation parameter corresponding to the first power in an embodiment of the present application. As shown in FIG. 4 , the processing flow of this step specifically includes:

S010, when the radio frequency circuit outputs the first power, obtain the first digital gain of the digital adjustable gain module in the radio frequency circuit, and obtain the first analog gain of the analog adjustable gain module in the radio frequency circuit;

S020, acquiring the first feedback signal when the radio frequency circuit outputs the first power;

S030. Determine a first compensation parameter according to the first digital gain, the first analog gain, and the first feedback signal;

S040. Save the correspondence between the first power and the first compensation parameter.

Specifically, determining the first compensation parameter corresponding to the first power may be implemented by a predistortion parameter estimation module in the radio frequency circuit, and the predistortion parameter estimation module obtains the first digital gain, the first analog gain and the first digital gain corresponding to the first power. After the feedback signal, the first compensation parameter can be determined by modeling.

Among them, the baseband model of the power amplifier is as follows:

y _avga = y*g _avga

Among them, z is the output signal of the power amplifier, yavga is the output signal of the analog adjustable gain module, y is the output signal of the predistorter, gavga is the gain of the analog adjustable gain module, Q(q) is the nonlinear order, M(m) is the memory depth, a _g,m is the compensation parameter, and n is the serial number of the current data.

When referenced to point y, the model of the power amplifier is as follows:

According to the above formula, it can be known that the model of the power amplifier changes with the change of the gain gavga of the analog adjustable gain module.

In addition, the model of the predistorter is as follows:

x _dvga = x*g _dvga

Among them, y is the output signal of the predistorter, xdvga is the output of the digital adjustable gain module, x is the input signal, gdvga is the gain of the digital adjustable gain module, Q(q) is the nonlinear order, M(m) is the memory depth, w is the predistortion compensation parameter, and n is the serial number of the current data.

The function of the predistorter is to make: z(n)≈gc(n) at the output of the power amplifier, where g is the total gain of the digital gain and the analog gain. In order to make the gain of the predistorter 1, it is necessary to align the power of the digital feedback signal zfb, that is, there is g _att to make the average power of z _fb and x _dvga equal, and g _att is the gain adjustment of the adjustable attenuator.

Modeling with x _dvga as input and z _fb as output such that:

From the above formula can be obtained:

f _dpd (x)≈g _att ^-1 f _pa ^-1 (y)

From z _fb , x _dvga can estimate w _q,m in f _dpd (x) such that:

z _fb (n)≈x _dvga

which is:

Therefore, based on the above formula, the predistortion parameter estimation module can obtain the first compensation parameter w _q,m through modeling.

When the output power of the power amplifier changes, the digital feedback signal z _fb will also change. In order to make z _fb (n)≈x _dvga , it is necessary to re-determine w _q,m . For the processing process, refer to the above-mentioned embodiments. The content will not be repeated here.

It should be understood that, although the steps in the flow charts in the above embodiments are sequentially displayed according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, the execution of these steps is not strictly limited to the order and may be performed in other orders. Moreover, at least a part of the steps in the figure may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily executed at the same time, but may be executed at different times, and the execution order is not necessarily sequential. Instead, it may be performed in turn or alternately with other steps or at least a portion of sub-steps or stages of other steps.

In some embodiments, a predistortion compensation apparatus for a radio frequency circuit is provided. FIG. 5 is a schematic diagram of a predistortion compensation device for a radio frequency circuit provided by an embodiment of the present application. As shown in FIG. 5 , the device includes:

a first determination module 100, configured to determine the target output power of the radio frequency circuit;

The second determination module 200 is configured to determine the second compensation parameter and the gain adjustment amount corresponding to the target output power according to the pre-stored first power and the first compensation parameter corresponding to the first power, wherein the first compensation parameter is a radio frequency circuit The output power is the corresponding predistortion compensation parameter of the first power, and the first power is any power within the output power range of the radio frequency circuit;

The processing module 300 is configured to configure the second compensation parameter to the predistorter in the radio frequency circuit, and adjust the gain of the radio frequency circuit according to the gain adjustment amount, so that the output power of the radio frequency circuit reaches the target output power.

For the specific limitation of the digital predistortion compensation apparatus, reference may be made to the limitation of the digital predistortion compensation method above, which will not be repeated here. Each module in the above-mentioned digital pre-distortion compensation apparatus may be implemented in whole or in part by software, hardware, and combinations thereof. The above modules can be embedded in or independent of the processor in the computer device in the form of hardware, or stored in the memory in the computer device in the form of software, so that the processor can call and execute the operations corresponding to the above modules.

The present application provides a digital predistortion compensation device, which firstly pre-stores the pre-distortion compensation parameters corresponding to any output power level. When signals of other power levels need to be output, other power levels can be calculated according to the pre-stored compensation parameters. Therefore, since there is no need to maintain the parameters corresponding to all power levels, on the one hand, when the working environment changes, it is only necessary to re-determine the compensation parameters corresponding to one power level, which can reduce the amount of calculation and avoid Frequent training signals are sent over the air to reduce interference to other devices; on the other hand, it can also reduce memory usage.

In some embodiments, an electronic device is provided, and the electronic device includes the radio frequency circuit of each of the above embodiments.

In some embodiments, a computer-readable storage medium is provided, and computer-executable instructions are stored in the computer-readable storage medium, and when the computer-executable instructions are executed by a processor, are used to implement the steps of each method embodiment of the present application.

In some embodiments, a computer program product is provided, including a computer program that, when executed by a processor, implements the steps of each method embodiment of the present application.

Those of ordinary skill in the art can understand that all or part of the processes in the methods of the above embodiments can be implemented by instructing relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium, When the computer program is executed, it may include the processes of the above-mentioned method embodiments. Wherein, any reference to memory, storage, database or other medium used in the various embodiments provided in this application may include non-volatile and/or volatile memory. Nonvolatile memory may include read only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous chain Road (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

Other embodiments of the present disclosure will readily occur to those skilled in the art upon consideration of the specification and practice of the applications disclosed herein. This application is intended to cover any variations, uses, or adaptations of the present disclosure that follow the general principles of the present disclosure and include common knowledge or techniques in the technical field not disclosed by the present disclosure . The specification and examples are to be regarded as exemplary only, with the true scope and spirit of the disclosure being indicated by the following claims.

It is to be understood that the present disclosure is not limited to the precise structures described above and illustrated in the accompanying drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

Claims

A predistortion compensation method for a radio frequency circuit, comprising:

Determine the target output power of the RF circuit;

Determine the second compensation parameter and the gain adjustment amount corresponding to the target output power according to the pre-stored first power and the first compensation parameter corresponding to the first power, wherein the first compensation parameter is the radio frequency circuit When the output power is the corresponding predistortion compensation parameter of the first power, the first power is any power within the output power range of the radio frequency circuit;

Configuring the second compensation parameter to a predistorter in the radio frequency circuit, and adjusting the gain of the radio frequency circuit according to the gain adjustment amount, so that the output power of the radio frequency circuit reaches the target output power .
The method according to claim 1, wherein the second compensation parameter and gain adjustment corresponding to the target output power are determined according to the pre-stored first power and the first compensation parameter corresponding to the first power amount, including:

Determine the gain adjustment amount according to the difference between the first power and the target output power;

The second compensation parameter is determined according to the gain adjustment amount and the first compensation parameter.
The method according to claim 2, wherein the determining the second compensation parameter according to the gain adjustment amount and the first compensation parameter comprises:

Allocating the gain adjustment amount to obtain an analog gain adjustment amount;

The second compensation parameter is determined according to the analog gain adjustment amount and the first compensation parameter.
The method according to claim 3, wherein the determining the second compensation parameter according to the analog gain adjustment amount and the first compensation parameter comprises:

The second compensation parameter is calculated by the following formula:

w c q,m =w ref q,m *(g ca (q-1) )

Among them, w c q,m is the second compensation parameter, w refq,m is the first compensation parameter, G ca is the analog gain adjustment amount, g ca is the linear value of the analog gain adjustment amount, q is the nonlinear order, and m is the memory depth.
The method according to claim 1, wherein the performing gain adjustment on the radio frequency circuit according to the gain adjustment amount comprises:

Allocate the gain adjustment amount to obtain a digital gain adjustment amount and an analog gain adjustment amount;

According to the digital gain adjustment amount, digital gain adjustment is performed on the digitally adjustable gain module in the radio frequency circuit;

According to the analog gain adjustment amount, the analog gain adjustment is performed on the analog adjustable gain module in the radio frequency circuit.
The method according to claim 3 or 5, wherein the allocating the gain adjustment amount comprises:

The integer part of the gain adjustment amount is assigned as the analog gain adjustment amount, and the fractional part of the gain adjustment amount is assigned as the digital gain adjustment amount.
The method of claim 1, further comprising:

When the radio frequency circuit outputs the first power, acquiring the first digital gain of the digital adjustable gain module in the radio frequency circuit, and acquiring the first analog gain of the analog adjustable gain module in the radio frequency circuit;

acquiring a first feedback signal when the radio frequency circuit outputs the first power;

determining the first compensation parameter according to the first digital gain, the first analog gain and the first feedback signal;

The corresponding relationship between the first power and the first compensation parameter is saved.
A predistortion compensation device for a radio frequency circuit, comprising:

a first determining module, used for determining the target output power of the radio frequency circuit;

A second determination module, configured to determine a second compensation parameter and a gain adjustment amount corresponding to the target output power according to the pre-stored first power and the first compensation parameter corresponding to the first power, wherein the first The compensation parameter is the corresponding predistortion compensation parameter when the output power of the radio frequency circuit is the first power, and the first power is any power within the output power range of the radio frequency circuit;

A processing module configured to configure the second compensation parameter to a predistorter in the radio frequency circuit, and perform gain adjustment on the radio frequency circuit according to the gain adjustment amount, so that the output power of the radio frequency circuit reaches the target output power.
A radio frequency circuit, comprising: a gain distribution module, a digital adjustable gain module, a predistorter, a predistortion parameter estimation module, an analog adjustable gain module, a power amplifier and a feedback module;

The digitally adjustable gain module is used to adjust the power of the input signal, and send the obtained first output signal to the predistorter and the predistortion parameter estimation module respectively;

The predistorter is configured to perform predistortion processing on the first output signal, and send the obtained second output signal to the analog adjustable gain module;

The analog adjustable gain module is used to adjust the power of the second output signal, and send the obtained third output signal to the power amplifier;

The power amplifier is configured to perform power amplification on the third output signal, send the obtained fourth output signal to the feedback module, and output the fourth output signal;

The feedback module is configured to generate a feedback signal based on the fourth output signal, and send the feedback signal to the predistortion parameter estimation module;

The predistortion parameter estimation module is configured to determine a compensation parameter of the predistorter according to the first output signal and the feedback signal, and configure the compensation parameter to the predistorter;

The gain distribution module is used for gain distribution to the digital adjustable gain module and the analog adjustable gain module.
An electronic device, characterized by comprising the radio frequency circuit as claimed in claim 9 .