CN-121664212-B - Nonlinear second harmonic distortion correction method, nonlinear second harmonic distortion correction device, nonlinear second harmonic distortion correction equipment and storage medium

CN121664212BCN 121664212 BCN121664212 BCN 121664212BCN-121664212-B

Abstract

The invention discloses a nonlinear second harmonic distortion correction method, a nonlinear second harmonic distortion correction device, nonlinear second harmonic distortion correction equipment and a storage medium, wherein the nonlinear second harmonic distortion correction method comprises the steps of responding to a calibration trigger signal to generate a test signal with preset frequency after receiving the calibration trigger signal; and receiving the radio frequency service signal, performing nonlinear compensation on the radio frequency service signal based on the compensation parameter, and obtaining and outputting the compensated radio frequency service signal. Because the invention responds to the calibration trigger signal to generate the test signal, then based on the statistical distribution characteristic of the test signal, the compensation parameter for inhibiting the second harmonic distortion is determined, and finally, the nonlinear compensation is carried out on the radio frequency service signal based on the compensation parameter.

Inventors

LIN ZIQI
HE HONGYIN
LIU XINFANG
WANG RIYAN
CHEN ZIFAN
LIU YI

Assignees

广州润芯信息技术有限公司

Dates

Publication Date: 20260508
Application Date: 20260209

Claims (9)

1. A method of nonlinear second harmonic distortion correction, the method comprising: After receiving a calibration trigger signal, generating a test signal with preset frequency in response to the calibration trigger signal; Determining a compensation parameter for suppressing second harmonic distortion based on the statistical distribution characteristic of the test signal; Receiving a radio frequency service signal, carrying out nonlinear compensation on the radio frequency service signal based on the compensation parameter, and obtaining and outputting a compensated radio frequency service signal; The step of determining a compensation parameter for suppressing second harmonic distortion based on the statistical distribution characteristic of the test signal includes: Collecting and caching a preset number of data points of the test signals; Determining a bias value of an output signal of the test signal after nonlinear transformation based on the preset number of data points, and taking the bias value as a statistical distribution characteristic of the test signal, wherein the nonlinear transformation comprises a compensation parameter to be determined; iteratively updating the compensation parameters by taking the absolute value of the minimum bias value as an optimization target; and when the absolute value of the bias value in the iterative updating process meets a preset convergence condition, taking the current compensation parameter as the compensation parameter for inhibiting the second harmonic distortion.
2. The method of claim 1, wherein the step of determining a bias value of the output signal of the test signal after nonlinear transformation based on the predetermined number of data points, and using the bias value as a statistical distribution characteristic of the test signal comprises: Based on the preset number of data points, determining the mean value and standard deviation of the output signals of the test signals after nonlinear transformation; determining a third-order center moment of the output signal based on the mean value and the preset number of data points; and determining a bias value according to the third-order central moment and the standard deviation, and taking the bias value as the statistical distribution characteristic of the test signal.
3. The nonlinear second harmonic distortion correction method as claimed in claim 1, wherein the step of iteratively updating the compensation parameter with an absolute value that minimizes the offset value as an optimization target comprises: Constructing a cost function based on the absolute value of the bias value, and determining the gradient of the cost function with respect to the compensation parameter; And updating the compensation parameter by using a gradient descent method based on the gradient until the absolute value of the bias value meets a preset convergence condition.
4. The nonlinear second harmonic distortion correction method as set forth in claim 1, wherein the step of generating a test signal of a preset frequency in response to a calibration trigger signal after receiving the calibration trigger signal, comprises: Generating a test signal acquisition request signal in response to the calibration trigger signal; and based on the test signal acquisition request signal, controlling the auxiliary phase-locked loop to generate a single-frequency signal with a preset frequency, and taking the single-frequency signal as a test signal.
5. The nonlinear second harmonic distortion correction method as set forth in claim 1, wherein the step of receiving the rf service signal and nonlinear compensating the rf service signal based on the compensation parameter, obtaining and outputting the compensated rf service signal comprises: receiving a radio frequency service signal, and determining an in-phase branch signal and a quadrature branch signal in the radio frequency service signal; Based on the compensation parameters, respectively carrying out nonlinear compensation on the in-phase branch signal and the quadrature branch signal to obtain a compensated in-phase branch signal and a compensated quadrature branch signal; and taking the compensated in-phase branch signal and the compensated quadrature branch signal as compensated radio frequency service signals.
6. The method for nonlinear second harmonic distortion correction as in any one of claims 1-5, further comprising, prior to the step of nonlinear compensating the radio frequency traffic signal based on the compensation parameter: judging whether the compensation enabling signal is valid or not; if the compensation enabling signal is valid, executing a step of nonlinear compensation of the radio frequency service signal based on the compensation parameter; and if the compensation enabling signal is invalid, bypassing the step of performing nonlinear compensation on the radio frequency service signal based on the compensation parameter, and outputting the radio frequency service signal.
7. A nonlinear second harmonic distortion correction apparatus, the apparatus comprising: The signal generation module is used for responding to the calibration trigger signal to generate a test signal with preset frequency after receiving the calibration trigger signal; the parameter determining module is used for determining a compensation parameter for suppressing second harmonic distortion based on the statistical distribution characteristic of the test signal; the signal processing module is used for receiving the radio frequency service signal, carrying out nonlinear compensation on the radio frequency service signal based on the compensation parameter, and obtaining and outputting the compensated radio frequency service signal; The parameter determining module is further configured to collect and buffer a preset number of data points of the test signal, determine a bias value of an output signal of the test signal after nonlinear transformation based on the preset number of data points, and use the bias value as a statistical distribution characteristic of the test signal, wherein the nonlinear transformation includes a compensation parameter to be determined, and iteratively update the compensation parameter with an absolute value of minimizing the bias value as an optimization target, and when the absolute value of the bias value meets a preset convergence condition in an iterative update process, use the current compensation parameter as a compensation parameter for suppressing second harmonic distortion.
8. A nonlinear second harmonic distortion correction apparatus comprising a memory, a processor, and a nonlinear second harmonic distortion correction program stored on the memory and executable on the processor, the nonlinear second harmonic distortion correction program configured to implement the steps of the nonlinear second harmonic distortion correction method of any one of claims 1-6.
9. A storage medium having stored thereon a nonlinear second harmonic distortion correction program which when executed by a processor implements the steps of the nonlinear second harmonic distortion correction method of any of claims 1 to 6.

Description

Nonlinear second harmonic distortion correction method, nonlinear second harmonic distortion correction device, nonlinear second harmonic distortion correction equipment and storage medium Technical Field The present invention relates to the field of wireless communications technologies, and in particular, to a nonlinear second harmonic distortion correction method, apparatus, device, and storage medium. Background In modern wireless communication systems, particularly in high frequency broadband systems such as 5G NR, millimeter wave communication, and satellite communication, the radio frequency receiver front end includes nonlinear devices such as Low Noise Amplifiers (LNAs), mixers, analog-to-digital converters (ADCs), and the like. These devices introduce nonlinear distortion during signal processing, with second harmonic distortion (HD 2) being a particular problem. The frequency of the second harmonic component is twice of the carrier frequency of the input signal, which is easy to fall into the target signal frequency band or the adjacent channel thereof in a broadband system (such as OFDM), so that the frequency spectrum pollution and the Adjacent Channel Leakage Ratio (ACLR) are deteriorated, the signal-to-noise ratio (SNR) and the sensitivity of a receiver are obviously reduced, and the overall bit error rate performance of the system is further affected. In order to suppress the second harmonic distortion, various technical schemes have been proposed. The Digital Predistortion (DPD) technology counteracts distortion by injecting reverse nonlinearity into the front end of a signal chain, but the method needs to accurately model nonlinear characteristics of a system, usually involves complex operations such as higher order polynomial inversion, has heavy computational burden, and is difficult to deploy in a radio frequency chip with limited resources or a real-time processing scene requiring low delay. The adaptive filtering technology (such as LMS and RLS algorithms) dynamically adjusts the filter coefficient through error feedback to inhibit distortion, but the convergence speed and stability of the adaptive filtering technology face challenges under the condition of rapid channel change or broadband signals, and real-time performance is difficult to guarantee. Therefore, a nonlinear second harmonic distortion correction method is needed to effectively reduce the computation complexity and improve the real-time performance. Disclosure of Invention The invention mainly aims to provide a nonlinear second harmonic distortion correction method, device, equipment and storage medium, and aims to solve the technical problems of higher computational complexity and poorer real-time performance of the existing second harmonic distortion correction technology. To achieve the above object, the present invention provides a nonlinear second harmonic distortion correction method comprising the steps of: After receiving a calibration trigger signal, generating a test signal with preset frequency in response to the calibration trigger signal; Determining a compensation parameter for suppressing second harmonic distortion based on the statistical distribution characteristic of the test signal; and receiving a radio frequency service signal, carrying out nonlinear compensation on the radio frequency service signal based on the compensation parameter, and obtaining and outputting a compensated radio frequency service signal. Optionally, the step of determining the compensation parameter for suppressing the second harmonic distortion based on the statistical distribution characteristic of the test signal includes: Collecting and caching a preset number of data points of the test signals; Determining a bias value of an output signal of the test signal after nonlinear transformation based on the preset number of data points, and taking the bias value as a statistical distribution characteristic of the test signal, wherein the nonlinear transformation comprises a compensation parameter to be determined; iteratively updating the compensation parameters by taking the absolute value of the minimum bias value as an optimization target; and when the absolute value of the bias value in the iterative updating process meets a preset convergence condition, taking the current compensation parameter as the compensation parameter for inhibiting the second harmonic distortion. Optionally, the step of determining a bias value of the output signal of the test signal after nonlinear transformation based on the preset number of data points, and taking the bias value as the statistical distribution characteristic of the test signal includes: Based on the preset number of data points, determining the mean value and standard deviation of the output signals of the test signals after nonlinear transformation; determining a third-order center moment of the output signal based on the mean value and the preset number of data points; and determ