Broadband high-precision voltage compensation control method of power amplifier

Abstract

The invention discloses a broadband high-precision voltage compensation control method of a power amplifier, relates to the technical field of broadband compensation, and is used for solving the problem of low voltage compensation efficiency caused by cooperative distortion caused by mutual regulation and control when the signal frequencies of different input channels are close. Recording information of the input signal is called to judge the signal type of the input signal, when the multi-frequency signal exists in the analysis database, the signal amplitude and the signal frequency of the multi-frequency signal are collected, the high-order intermodulation distortion degree of the input signal is judged, and the distortion index of the multi-frequency signal is calculated; selecting to start intermodulation distortion processing or enter a frequency coexistence risk test mechanism according to the high-order intermodulation distortion degree of the multi-frequency signals, calculating frequency intermodulation characteristics of different single-frequency signals, and performing effect integration on the frequency intermodulation characteristics of all the single-frequency signals in the analysis database according to the number of the single-frequency signals; and judging whether to carry out intermodulation distortion processing or not by combining the distortion index of the multi-frequency signal.

Description

Technical Field

[0001] The present invention relates to the technical field of broadband compensation, and more particularly to a broadband high-precision voltage compensation control method for a power amplifier. Background Art

[0002] Wideband compensation technology is a technology widely used in the fields of communications and signal processing, aiming to improve system performance under wide-band conditions. The application of wideband compensation technology in power amplifier voltage regulation can ensure stable voltage input and output, thereby ensuring work efficiency.

[0003] The existing technology has the following deficiencies:

[0004] In the past, when using power amplifiers to compensate for broadband, high-precision voltage, the only consideration was adding inputs to compensate for insufficient voltage supply to allow the voltage to complete the operation. However, the number of input signal frequencies and the cooperative distortion caused by mutual regulation when the frequencies of different input channel signals were close were not considered when adding inputs. This resulted in inefficient voltage compensation. Summary of the Invention

[0005] In order to overcome the above-mentioned defects of the prior art, an embodiment of the present invention provides a wide-band, high-precision voltage compensation control method for a power amplifier. By analyzing the number of signal frequencies in different input signals when the power amplifier performs voltage compensation and judging the intermodulation and cooperative distortion influence of each input channel, it is determined whether intermodulation distortion processing should be performed first and then compensation to solve the problems raised in the above-mentioned background technology.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a broadband high-precision voltage compensation control method for a power amplifier, comprising the following steps:

[0007] Step S1: Detecting the input signal in real time, adding it to the analysis database and recording information of the input signal, calling the recorded information of the input signal to determine the signal type of the input signal, and classifying and marking the input signal as a single-frequency signal or a multi-frequency signal according to the signal type;

[0008] Step S2: When a multi-frequency signal exists in the analysis database, the signal amplitude and signal frequency of the multi-frequency signal are collected; the signal amplitude and signal frequency of the multi-frequency signal are comprehensively used to determine the degree of high-order intermodulation distortion of the input signal and calculate the distortion index of the multi-frequency signal;

[0009] Step S3: selecting to enable intermodulation distortion processing or enter a frequency coexistence risk verification mechanism based on the degree of high-order intermodulation distortion of the multi-frequency signal; in the frequency coexistence risk verification mechanism, statistically analyzing the number of single-frequency signals in the database;

[0010] Step S4: Set the reference signal frequency, compare the signal frequency of each single-frequency signal in the analysis database with the reference signal frequency and calculate the frequency intermodulation characteristics of different single-frequency signals, integrate the effects of the frequency intermodulation characteristics of all single-frequency signals in the analysis database according to the number of single-frequency signals, and determine whether to perform intermodulation distortion processing based on the integrated effect results of the single-frequency signals and the distortion index of the multi-frequency signals.

[0011] In a preferred embodiment, in step S1, the recorded information of the input signal is a spectrum diagram of the input signal, and the spectrum diagram includes the signal frequency and peak amplitude of the input signal;

[0012] If only one peak amplitude in the input signal exceeds the preset amplitude threshold, it is marked as a single-frequency signal; if multiple signal peak amplitudes in the input signal exceed the preset amplitude threshold, it is marked as a multi-frequency signal;

[0013] The signal frequency and peak amplitude of the input signal in the spectrum graph are merged into a frequency set F and an amplitude set A respectively.

[0014] In a preferred embodiment, in step S2, the frequency set F and the amplitude set A of the multi-frequency signal are retrieved from the analysis database to analyze the intermodulation product frequencies. The specific steps are as follows:

[0015] Frequency offset calculation: Select the lowest frequency from the frequency set F, subtract the data in the frequency set from the lowest frequency to obtain the relative offset of each signal frequency, and combine the relative offsets of each signal frequency into a frequency offset set;

[0016] Third-order intermodulation product analysis: Randomly select the relative offset of two signal frequencies in the frequency offset set and calculate the original intermodulation product frequency between the two signal frequencies: Where i and j are two signal numbers with different values. The actual intermodulation product frequency is calculated based on the original intermodulation product frequency: f IMD =f min +Δf IMD .

[0017] In a preferred embodiment, in step S2, when the actual intermodulation product f calculated by the two signal frequencies is IMD If the frequency is between the lowest and highest frequencies in the frequency set, the peak amplitudes under the spectrum graph corresponding to the two signal frequencies are screened out, the actual intermodulation product is calculated once for every two signal frequencies, and the screened peak amplitudes are combined into the intermodulation product amplitude set.

[0018] In a preferred embodiment, in step S2, the average value of all peak amplitudes in the intermodulation product amplitude set is calculated, which is recorded as A μ , according to A μ Calculate the intermodulation product amplitude: Among them, a1, a2 are the first-order and third-order coefficients of the nonlinear system; the intermodulation product is generated by the interaction of the two signal frequencies, A i is the first peak amplitude, A j is the second peak amplitude, A IMD3 is the intermodulation product amplitude.

[0019] The degree of high-order intermodulation distortion of the multi-frequency signal is determined as follows: if there is at least one intermodulation product whose amplitude is greater than a preset amplitude threshold, it is determined to be a high distortion degree; if all intermodulation product amplitudes are less than the preset amplitude threshold, it is determined to be a low distortion degree;

[0020] The calculation formula for the multi-frequency signal distortion index is:

[0021] In a preferred embodiment, in step S3, when the high-order intermodulation distortion of the multi-frequency signal is determined to be a high degree of distortion, intermodulation distortion processing is performed by a feedback loop method;

[0022] The real-time monitoring output signal of the feedback loop is recorded as x out (t), the input signal is denoted as x in (t), the output signal is subtracted from the input signal to extract the intermodulation product, e(t) is converted into a spectrum by fast Fourier transform, and the signal amplitude and signal frequency of the intermodulation product are extracted;

[0023] When the signal amplitude of the intermodulation product is greater than the product amplitude threshold, the gain change of the amplifier is adjusted to suppress it: ΔG = -k p ·A IMD3 -k i ∫A IMD3 dt, where k p is the proportionality coefficient, k i is the integral coefficient, and ΔG is the gain change of the amplifier.

[0024] In a preferred embodiment, in step S3, when the high-order intermodulation distortion of the multi-frequency signal is judged to be low-level distortion, the frequency coexistence risk detection mechanism is entered, the number of single-frequency signals is counted, and their frequency intermodulation characteristics are analyzed as follows:

[0025] The working bandwidth of the power amplifier is divided into multiple sub-bands, the single-frequency signals in the analysis database are extracted, and the number of single-frequency signals in each sub-band is counted, which is recorded as N:{N 1, N 2,..., N n}, where N i, is the number of single-frequency signals in the ith sub-band, N is the total number of sub-bands, and the sub-band signal density is calculated as:

[0026]

[0027] Select a period of time in the past as a sample, calculate the average and standard deviation of the sub-band signal density, and use the sum of the average and standard deviation of the sub-band signal density as the risk threshold;

[0028] When the signal density of a sub-band is higher than the risk threshold, the sub-band is marked as a high-risk area; when the signal density of a sub-band is lower than the risk threshold, the sub-band is marked as a low-risk area.

[0029] In a preferred embodiment, in step S4, the frequency intermodulation characteristic of the single-frequency signal is the frequency difference of the single-frequency signal, the frequency set F of the multi-frequency signal is extracted from the analysis database, and the average value of the multi-frequency signal frequency is calculated as the reference signal frequency, marked as f base ;

[0030] The frequency difference is obtained by taking the absolute value of the difference between the signal frequency of the single-frequency signal in the analysis database and the reference signal frequency: Δf k =|f k -f base |, where f k is the signal frequency of the single-frequency signal, Δf k is the frequency difference.

[0031] In a preferred embodiment, in step S4, the frequency difference is divided into different difference intervals, and the risk interval is divided into different intervals by a frequency difference threshold;

[0032] If the frequency difference exceeds the frequency difference threshold, it is judged as a high-risk interval; if the frequency difference is lower than the frequency difference threshold, it is judged as a low-risk interval;

[0033] When the number of single-frequency signals in the high-risk range in the sub-frequency band exceeds the single-frequency high-risk threshold and the number of single-frequency signals exceeds the preset sub-frequency band signal threshold, the sub-frequency band is integrated; otherwise, no effect integration is performed;

[0034] When integrating the effects of sub-frequency bands, the sub-frequency band with the largest number of single-frequency signals is selected for marking, and the marked sub-frequency band is used as the effect integration result.

[0035] In a preferred embodiment, in step S4, the effect integration result of the single-frequency signal and the distortion index of the multi-frequency signal are combined to determine whether to perform intermodulation distortion processing. The judgment rules are as follows:

[0036] If the multi-frequency signal distortion index is greater than the distortion index threshold, it is judged as high distortion, and the feedback loop method is directly triggered to perform intermodulation distortion processing; if the multi-frequency signal distortion index is lower than the distortion index threshold, it is judged as low distortion;

[0037] When the judgment result is low distortion, if the sub-frequency band is marked as a high-risk area, intermodulation distortion processing is performed; if the sub-frequency band is marked as a low-risk area, intermodulation distortion processing is not performed.

[0038] Technical effects and advantages of the present invention:

[0039] The present invention incorporates input signals into an analysis database through real-time detection and records information of the input signals, calls the recorded information of the input signals to determine the signal type of the input signals, reduces detection costs, and provides detection directions. When a multi-frequency signal exists in the analysis database, the signal amplitude and signal frequency of the multi-frequency signal are collected, the high-order intermodulation distortion degree of the input signal is determined, and the distortion index of the multi-frequency signal is calculated. According to the high-order intermodulation distortion degree of the multi-frequency signal, intermodulation distortion processing is selected to be enabled or a frequency coexistence risk verification mechanism is entered. The frequency coexistence risk verification mechanism is entered to further verify the coordinated regulation distortion influence of different input channels, improve the voltage compensation efficiency, calculate the frequency intermodulation characteristics of different single-frequency signals, integrate the effects of the frequency intermodulation characteristics of all single-frequency signals in the analysis database according to the number of single-frequency signals, and determine whether to perform intermodulation distortion processing in combination with the distortion index of the multi-frequency signal, thereby improving the reliability and stability of the system, reducing intermodulation interference and signal distortion, and optimizing the use of spectrum resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 This is a flowchart of a wide-band, high-precision voltage compensation control method for a power amplifier according to the present invention. DETAILED DESCRIPTION

[0041] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0042] The present invention detects input signals in real time, incorporates them into an analysis database, records information about the input signals, calls the recorded information of the input signals to determine the signal type of the input signals, and when a multi-frequency signal exists in the analysis database, collects the signal amplitude and signal frequency of the multi-frequency signal, determines the degree of high-order intermodulation distortion of the input signal, and calculates the distortion index of the multi-frequency signal. According to the degree of high-order intermodulation distortion of the multi-frequency signal, intermodulation distortion processing is selected to be enabled or a frequency coexistence risk detection mechanism is entered. Frequency intermodulation characteristics of different single-frequency signals are calculated, and the frequency intermodulation characteristics of all single-frequency signals in the analysis database are effect-integrated according to the number of single-frequency signals. In combination with the distortion index of the multi-frequency signal, it is determined whether intermodulation distortion processing should be performed, thereby improving the reliability and stability of the system, reducing intermodulation interference and signal distortion, and optimizing the use of spectrum resources.

[0043] Example 1, a wideband high-precision voltage compensation control method for a power amplifier, such as Figure 1 As shown, the following steps are included:

[0044] Step S1: Detecting the input signal in real time, adding it to the analysis database and recording information of the input signal, calling the recorded information of the input signal to determine the signal type of the input signal, and classifying and marking the input signal as a single-frequency signal or a multi-frequency signal according to the signal type;

[0045] Step S2: When a multi-frequency signal exists in the analysis database, the signal amplitude and signal frequency of the multi-frequency signal are collected; the signal amplitude and signal frequency of the multi-frequency signal are comprehensively used to determine the degree of high-order intermodulation distortion of the input signal and calculate the distortion index of the multi-frequency signal;

[0046] Step S3: selecting to enable intermodulation distortion processing or enter a frequency coexistence risk verification mechanism based on the degree of high-order intermodulation distortion of the multi-frequency signal; in the frequency coexistence risk verification mechanism, statistically analyzing the number of single-frequency signals in the database;

[0047] Step S4: Set the reference signal frequency, compare the signal frequency of each single-frequency signal in the analysis database with the reference signal frequency and calculate the frequency intermodulation characteristics of different single-frequency signals, integrate the effects of the frequency intermodulation characteristics of all single-frequency signals in the analysis database according to the number of single-frequency signals, and determine whether to perform intermodulation distortion processing based on the integrated effect results of the single-frequency signals and the distortion index of the multi-frequency signals.

[0048] The specific implementation is as follows:

[0049] In step S1, the recorded information of the input signal is a spectrum diagram of the input signal, which includes the signal frequency and peak amplitude of the input signal. The input signal is collected as an analog signal by an analog-to-digital converter and converted into a digital signal. The digital signal is output as a spectrum diagram through a fast Fourier transform. The horizontal axis in the spectrum diagram represents the frequency point, that is, the signal frequency, and the vertical axis represents the amplitude, which includes the peak amplitude, that is, the maximum signal amplitude value at each signal frequency. The peak amplitude is used as the signal amplitude corresponding to the signal frequency; the signal type is distinguished by detecting the peak amplitude. The single-frequency signal has only one peak amplitude, and the multi-frequency signal contains multiple peak amplitudes.

[0050] Perform peak detection on the spectrum graph. If only one peak amplitude exceeds the preset amplitude threshold, it is marked as a single-frequency signal; if multiple signal peak amplitudes exceed the preset amplitude threshold, it is marked as a multi-frequency signal, and each signal frequency is stored separately; the signal frequency and peak amplitude of the input signal in the spectrum graph are merged into a frequency set and an amplitude set respectively, and transmitted to the analysis database in real time in combination with the signal type of the input signal.

[0051] It should be noted that a digital-to-analog converter is an electronic device that converts continuous analog signals into digital signals. In communication systems, wireless signals are sampled by the digital-to-analog converter and converted into digital signals for easy digital demodulation, encoding and transmission. An analysis database is a database used to store, manage and analyze real-time acquired signal parameters and data generated during the processing process. It is the data basis of the entire signal processing process and provides key functions for subsequent distortion evaluation and control strategy selection. Fast Fourier transform is an algorithm for efficiently calculating discrete Fourier transform, which can convert time domain signals into frequency domain signals. Through fast Fourier transform calculation, a signal spectrum diagram can be obtained. Fast Fourier transform can directly obtain a signal spectrum diagram with the help of Python's scientific computing library.

[0052] In step S2, under the influence of the nonlinear characteristics of the power amplifier, the multi-frequency signal input will produce high-order intermodulation distortion; the signal type marked as a multi-frequency signal is retrieved from the analysis database, and its frequency set and amplitude set are obtained, which are respectively recorded as F:{f1,f2,...f n}、A:{A1,A2,...A n}.

[0053] Before evaluating high-order intermodulation distortion (HOM) of multi-frequency signals, each signal frequency is normalized and converted into a relative frequency offset, which reflects the distance between each signal frequency and the lowest signal frequency. The smaller the interval, the more likely it is to cause intermodulation interference. In multi-frequency signals, the signal amplitudes corresponding to each signal frequency may be different, and the intermodulation products of strong signals have a greater impact on the system.

[0054] The relative amplitude difference of the signal amplitude is calculated to reflect the signal amplitude difference of each signal frequency. The specific calculation steps are as follows:

[0055] Get the lowest frequency from the frequency set F, denoted as f min =min(F), the frequency of each signal relative to f min The frequency offset is calculated as: Among them, f i is the signal frequency, i can take values of 1, 2, 3, etc. is the corresponding frequency offset; the frequency offsets of the data in the frequency set F are calculated separately and then merged into a frequency offset set, which is recorded as:

[0056] The degree of high-order intermodulation distortion also requires a comprehensive assessment of the frequency and amplitude of the intermodulation products. In this method, only third-order intermodulation products are calculated and analyzed, and the calculation of fifth-order intermodulation products is not involved.

[0057] f i 、f j The relative offsets are recorded as and i and j can take values of 1, 2, 3, etc. The formula for calculating the original intermodulation product frequency is: The actual intermodulation product frequency calculation formula is: f IMD =f min +Δf IMD , where f IMD is the actual intermodulation product frequency.

[0058] Actual intermodulation product frequency f IMD Falling within the signal bandwidth will interfere with the useful signal, and only the intermodulation products falling within the signal band will be retained. If the frequency f of the actual intermodulation product of the two signal frequencies is IMD Between the lowest frequency and the highest frequency in the frequency set; the peak amplitudes under the spectrum graph corresponding to the two signal frequencies are screened out, the actual intermodulation product is calculated once for every two signal frequencies, and the screened peak amplitudes are merged into the intermodulation product amplitude set A1.

[0059] In the intermodulation product amplitude set A1, the peak amplitudes corresponding to the various signal frequencies are different. The average value of all peak amplitudes in the intermodulation product amplitude set is calculated and recorded as A μ ;

[0060] The formula for calculating the intermodulation product amplitude is: Among them, a1, a2 are the first-order and third-order coefficients of the nonlinear system; the intermodulation product is generated by the interaction of the two signal frequencies, A i is the first peak amplitude, A jis the second peak amplitude, A IMD3 is the intermodulation product amplitude.

[0061] The high-order intermodulation distortion degree of the multi-frequency signal is determined as follows: if there is at least one intermodulation product whose amplitude is greater than a preset amplitude threshold, it is determined as a high distortion degree; if the amplitudes of all intermodulation products are less than the preset amplitude threshold, it is determined as a low distortion degree.

[0062] The multi-frequency signal distortion index can directly reflect the severity of multi-frequency signal distortion. The calculation formula of the multi-frequency signal distortion index is: DI is the multi-frequency signal distortion index. The smaller the multi-frequency signal distortion index, the more serious the distortion.

[0063] By quantifying the distortion risk through normalization and calculation of intermodulation products, a rapid evaluation system for the nonlinear distortion of multi-frequency signals was constructed. The multi-frequency signal distortion index provides a decision basis for step S3, thereby improving the linearity and anti-interference capability of the power amplifier.

[0064] It should be noted that intermodulation products are new frequency components generated due to the nonlinear characteristics of a nonlinear system when two or more signals of different frequencies are simultaneously input into a nonlinear system. For example, there are two signal frequencies f1 and f2 in a multi-frequency signal. Under the action of the nonlinear system, new signal frequency components such as mf1±nf2 will be generated, namely intermodulation products; third-order intermodulation products are a type of high-order intermodulation distortion. For example, in the above formula, the intermodulation product generated when m+n=3 is a third-order intermodulation product, and common forms are 2f1-f2 and 2f2-f1; the amplitude of the third-order intermodulation product is relatively large and may fall within the frequency band of the useful signal, thereby causing interference to the signal.

[0065] In step S3, when the high-order intermodulation distortion of the multi-frequency signal is judged to be a high degree of distortion, it indicates that the signal distortion is serious and has a great impact on the system performance. The intermodulation distortion is processed by the feedback loop method; the feedback loop real-time monitoring output signal is recorded as x out (t), the input signal is denoted as x in (t), the output signal and the input signal are subtracted to extract the intermodulation product, and the calculation formula is: e(t) = x in (t)-x out (t), where e(t) is the intermodulation product; e(t) is converted into a spectrum diagram by fast Fourier transform, and the signal amplitude and signal frequency of the intermodulation product are extracted.

[0066] When the signal amplitude of the intermodulation product is greater than the product amplitude threshold, the gain change of the amplifier is adjusted to suppress it. The calculation formula is: ΔG = -k p ·A IMD3 -k i ∫A IMD3 dt. Among them, kp is the proportionality coefficient, k i is the integral coefficient, and ΔG is the gain change of the amplifier.

[0067] The gain change ΔG of the adjusted amplifier is converted into an analog signal through a digital-to-analog converter, and the bias voltage or feedforward circuit of the amplifier is adjusted in real time. For example, by reducing the gain change of the amplifier, the operating point of the amplifier is adjusted to a more linear area, thereby reducing nonlinear distortion. After the adjustment is completed, the system will re-sample the output signal to verify the suppression effect of the intermodulation products.

[0068] When the high-order intermodulation distortion of the multi-frequency signal is judged to be low-level distortion, the frequency coexistence risk detection mechanism is entered. This mechanism handles the potential distortion risk by counting the number of single-frequency signals and analyzing their frequency intermodulation characteristics.

[0069] The power amplifier's operating bandwidth is divided into multiple sub-bands. Signal types marked as single-frequency signals in the analysis database are extracted, and the number of single-frequency signals within each sub-band is counted. For example, if the amplifier operates from 1 GHz to 6 GHz, each sub-band can be set to 100 MHz wide, and the entire band can be divided into 50 sub-bands.

[0070] The range of the sub-band is calculated as follows: Among them, Δf is the frequency coverage of the sub-band, f max and f min The total frequency range of the power amplifier currently operating, N sub is the total number of sub-bands.

[0071] Count the number of single-frequency signals in each sub-band, denoted as N:{N 1, N 2,..., N n}, where N i, is the number of single-frequency signals in the ith sub-band, i can take values of 1, 2, 3, etc., and N is the total number of sub-bands;

[0072] The signal density per unit bandwidth is further calculated to avoid statistical deviation caused by different frequency band widths. The calculation formula is: Where D(k) is the sub-band signal density.

[0073] Select the past period as a sample, calculate the average value and standard deviation of the sub-band signal density, and use the sum of the average value and standard deviation of the sub-band signal density as the risk threshold. The calculation formula is: D th =μ hist +σ, where μ hist is the average value of the sub-band signal density, σ is the standard deviation of the sub-band signal density, D th is the risk threshold.

[0074] When the signal density of a sub-band is higher than the risk threshold, the sub-band is marked as a high-risk area; when the signal density of a sub-band is lower than the risk threshold, the sub-band is marked as a low-risk area.

[0075] For high-level distortion, the feedback loop method is activated to monitor and adjust the amplifier gain in real time to suppress the third-order intermodulation products. For low-level distortion, the frequency coexistence risk detection mechanism is used to count the single-frequency signal density.

[0076] It should be noted that the goal of the feedback loop method is to suppress the nonlinear distortion of the power amplifier in real time and reduce the amplitude of the third-order intermodulation products; the frequency coexistence risk detection mechanism is an evaluation mechanism for low-level high-order intermodulation distortion. It avoids the risk of spectrum resource competition by real-time statistics of single-frequency signal density, dynamic risk assessment, and triggering prevention strategies; unit bandwidth signal density refers to the number of single-frequency signals existing in a unit frequency range, which is used to quantify the occupancy density of spectrum resources. Directly counting the number of signals cannot horizontally compare the loads of sub-bands of different widths, and solve the statistical deviation problem caused by differences in frequency band width; the output signal is the signal processed by the nonlinear system. The output signal contains the information of the original signal and the intermodulation products generated by nonlinear distortion.

[0077] In step S4, the frequency intermodulation feature of the single-frequency signal is the frequency difference of the single-frequency signal. The frequency set F of the multi-frequency signal is extracted from the analysis database, and the average value of the multi-frequency signal frequency is calculated as the reference signal frequency and marked as f base ;

[0078] The frequency difference is calculated by taking the absolute value of the difference between the signal frequency of the single-frequency signal in the analysis database and the reference signal frequency: Δf k =|f k -f base |, where f k is the signal frequency of the single-frequency signal, Δf k is the frequency difference;

[0079] The smaller the frequency difference is, the closer the single-frequency signal frequency is to the reference signal frequency, which may cause more adjacent intermodulation interference.

[0080] The frequency difference is divided into different difference intervals, and the risk interval is divided into different intervals according to the frequency difference threshold.

[0081] If the frequency difference exceeds the frequency difference threshold, it is judged as a high-risk interval; if the frequency difference is lower than the frequency difference threshold, it is judged as a low-risk interval; the risk intervals in which the single-frequency signal falls are counted and transmitted to the analysis database.

[0082] If the number of single-frequency signals in the high-risk range within the sub-frequency band exceeds the single-frequency high-risk threshold and the number of single-frequency signals exceeds the preset sub-frequency band signal threshold, the effect integration is performed on the sub-frequency band; otherwise, the effect integration is not performed.

[0083] When integrating the effects of sub-frequency bands, the sub-frequency band with the largest number of single-frequency signals is selected for marking, and the marked sub-frequency band is used as the effect integration result.

[0084] The effect integration result of the single-frequency signal and the distortion index of the multi-frequency signal are combined to determine whether intermodulation distortion processing should be performed. The specific judgment rules are as follows:

[0085] If the multi-frequency signal distortion index is greater than the distortion index threshold, it is judged as high distortion, and the feedback loop method is directly triggered to perform intermodulation distortion processing; if the multi-frequency signal distortion index is lower than the distortion index threshold, it is judged as low distortion;

[0086] When the judgment result is low distortion, if the sub-frequency band is marked as a high-risk area, intermodulation distortion processing is performed; if the sub-frequency band is marked as a low-risk area, intermodulation distortion processing is not performed.

[0087] Set the reference signal frequency, compare the frequency difference of single-frequency signals, divide the risk interval, integrate the intermodulation characteristics according to the number of signals in the high-risk interval, and dynamically determine the processing method based on the distortion index; effectively suppress distortion, improve system linearity, avoid spectrum competition risks, accurately assess potential distortion risks, and improve processing targeting and system stability.

[0088] It should be noted that effect integration is a comprehensive analysis of single-frequency signals to integrate more comprehensive intermodulation characteristics; intermodulation characteristics refer to the frequency relationship between single-frequency signals and multi-frequency signals. These relationships may cause the power amplifier to produce intermodulation distortion products. The prominent intermodulation characteristics refer to the intermodulation products that are very obvious and will cause interference due to small frequency differences or high signal strengths; the frequency difference threshold, sub-band signal threshold and single-frequency high-risk threshold are set as an interval range by professionals in this field. The threshold can be obtained by calculating the corresponding average value and standard deviation based on historical data. The method is not unique and will not be elaborated here.

[0089] The above formulas are all dimensionless and numerical calculations. The formulas are obtained by collecting a large amount of data and performing software simulation to obtain the most recent real situation. The preset parameters in the formulas are set by technicians in this field according to actual conditions.

[0090] The above embodiments can be implemented in whole or in part by software, hardware, firmware or any other combination. When implemented using software, the above embodiments can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions or computer programs. When the computer instructions or computer program are loaded or executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions can be transmitted from one website, computer, server or data center to another website, computer, server or data center via wired or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device such as a server or data center that contains one or more available media sets. The available medium can be a magnetic medium (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a DVD), or a semiconductor medium. The semiconductor medium can be a solid-state drive.

[0091] It should be understood that in the various embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0092] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0093] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0094] In the several embodiments provided in this application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of the units is merely a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0095] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0096] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0097] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0098] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. A method for controlling wideband and high-precision voltage compensation of a power amplifier, characterized by: The following steps are involved: Step S1: Detecting the input signal in real time, adding it to the analysis database and recording information of the input signal, calling the recorded information of the input signal to determine the signal type of the input signal, and classifying and marking the input signal as a single-frequency signal or a multi-frequency signal according to the signal type; Step S2: When a multi-frequency signal exists in the analysis database, the signal amplitude and signal frequency of the multi-frequency signal are collected; the signal amplitude and signal frequency of the multi-frequency signal are comprehensively used to determine the degree of high-order intermodulation distortion of the input signal and calculate the distortion index of the multi-frequency signal; Step S3: selecting to enable intermodulation distortion processing or enter a frequency coexistence risk verification mechanism based on the degree of high-order intermodulation distortion of the multi-frequency signal; in the frequency coexistence risk verification mechanism, statistically analyzing the number of single-frequency signals in the database; Step S4: Set the reference signal frequency, compare the signal frequency of each single-frequency signal in the analysis database with the reference signal frequency and calculate the frequency intermodulation characteristics of different single-frequency signals, integrate the effects of the frequency intermodulation characteristics of all single-frequency signals in the analysis database according to the number of single-frequency signals, and determine whether to perform intermodulation distortion processing based on the integrated effect results of the single-frequency signals and the distortion index of the multi-frequency signals.

2. The method for controlling wideband and high-precision voltage compensation of a power amplifier according to claim 1, wherein: In step S1, the recorded information of the input signal is a spectrum diagram of the input signal, and the spectrum diagram includes the signal frequency and peak amplitude of the input signal; If only one peak amplitude in the input signal exceeds the preset amplitude threshold, it is marked as a single-frequency signal; if multiple signal peak amplitudes in the input signal exceed the preset amplitude threshold, it is marked as a multi-frequency signal; The signal frequency and peak amplitude of the input signal in the spectrum graph are merged into a frequency set F and an amplitude set A respectively.

3. The method for controlling wideband and high-precision voltage compensation of a power amplifier according to claim 2, wherein: In step S2, the frequency set F and amplitude set A of the multi-frequency signal are retrieved from the analysis database to analyze the intermodulation product frequencies. The specific steps are as follows: Frequency offset calculation: Select the lowest frequency from the frequency set F, subtract the data in the frequency set from the lowest frequency to obtain the relative offset of each signal frequency, and combine the relative offsets of each signal frequency into a frequency offset set; Third-order intermodulation product analysis: Randomly select the relative offset of two signal frequencies in the frequency offset set and calculate the original intermodulation product frequency between the two signal frequencies: Where i and j are two signal numbers with different values. The actual intermodulation product frequency is calculated based on the original intermodulation product frequency: f IMD =f min +Δf IMD .

4. The method for controlling wideband and high-precision voltage compensation of a power amplifier according to claim 3, wherein: In step S2, when the actual intermodulation product f of the two signal frequencies is calculated IMD If the frequency is between the lowest and highest frequencies in the frequency set, the peak amplitudes under the spectrum graph corresponding to the two signal frequencies are screened out, the actual intermodulation product is calculated once for every two signal frequencies, and the screened peak amplitudes are combined into the intermodulation product amplitude set.

5. The method for controlling wideband and high-precision voltage compensation of a power amplifier according to claim 4, wherein: In step S2, the average value of all peak amplitudes in the intermodulation product amplitude set is calculated and recorded as A μ , according to A μ Calculate the intermodulation product amplitude: Among them, a1, a2 are the first-order and third-order coefficients of the nonlinear system; the intermodulation product is generated by the interaction of the two signal frequencies, A i is the first peak amplitude, A j is the second peak amplitude, A IMD3 is the intermodulation product amplitude. The degree of high-order intermodulation distortion of the multi-frequency signal is determined as follows: if there is at least one intermodulation product whose amplitude is greater than a preset amplitude threshold, it is determined to be a high distortion degree; if all intermodulation product amplitudes are less than the preset amplitude threshold, it is determined to be a low distortion degree; The calculation formula for the multi-frequency signal distortion index is:

6. The method for controlling wideband and high-precision voltage compensation of a power amplifier according to claim 5, wherein: In step S3, when the high-order intermodulation distortion of the multi-frequency signal is determined to be a high degree of distortion, intermodulation distortion processing is performed through a feedback loop method; The real-time monitoring output signal of the feedback loop is recorded as x out (t), the input signal is denoted as x in (t), the output signal is subtracted from the input signal to extract the intermodulation product, e(t) is converted into a spectrum by fast Fourier transform, and the signal amplitude and signal frequency of the intermodulation product are extracted; When the signal amplitude of the intermodulation product is greater than the product amplitude threshold, the gain change of the amplifier is adjusted to suppress it: ΔG = -k p ·A IMD3 -k i ∫A IMD3 dt, where k p is the proportionality coefficient, k i is the integral coefficient, and ΔG is the gain change of the amplifier.

7. The method for controlling wideband and high-precision voltage compensation of a power amplifier according to claim 5, wherein: In step S3, when the high-order intermodulation distortion of the multi-frequency signal is judged to be low-level distortion, the frequency coexistence risk detection mechanism is entered to count the number of single-frequency signals and analyze their frequency intermodulation characteristics as follows: The working bandwidth of the power amplifier is divided into multiple sub-bands, the single-frequency signals in the analysis database are extracted, and the number of single-frequency signals in each sub-band is counted, which is recorded as N:{N 1, N 2,..., N n }, where N i, is the number of single-frequency signals in the ith sub-band, N is the total number of sub-bands, and the sub-band signal density is calculated as: Select a period of time in the past as a sample, calculate the average and standard deviation of the sub-band signal density, and use the sum of the average and standard deviation of the sub-band signal density as the risk threshold; When the signal density of a sub-band is higher than the risk threshold, the sub-band is marked as a high-risk area; when the signal density of a sub-band is lower than the risk threshold, the sub-band is marked as a low-risk area.

8. The method for controlling wideband and high-precision voltage compensation of a power amplifier according to claim 1, wherein: In step S4, the frequency intermodulation feature of the single-frequency signal is the frequency difference of the single-frequency signal. The frequency set F of the multi-frequency signal is extracted from the analysis database, and the average value of the multi-frequency signal frequency is calculated as the reference signal frequency, which is marked as f base ; The frequency difference is obtained by taking the absolute value of the difference between the signal frequency of the single-frequency signal in the analysis database and the reference signal frequency: Δf k =|f k -f base |, where f k is the signal frequency of the single-frequency signal, Δf k is the frequency difference.

9. The method for controlling wideband and high-precision voltage compensation of a power amplifier according to claim 8, wherein: In step S4, the frequency difference is divided into different difference intervals, and the risk interval is divided into different intervals by the frequency difference threshold; If the frequency difference exceeds the frequency difference threshold, it is judged as a high-risk interval; If the frequency difference is lower than the frequency difference threshold, it is judged to be a low-risk interval; When the number of single-frequency signals in the high-risk range in the sub-frequency band exceeds the single-frequency high-risk threshold and the number of single-frequency signals exceeds the preset sub-frequency band signal threshold, the sub-frequency band is integrated; Otherwise, no effect integration is performed; When integrating the effects of sub-frequency bands, the sub-frequency band with the largest number of single-frequency signals is selected for marking, and the marked sub-frequency band is used as the effect integration result.

10. The method for controlling wideband and high-precision voltage compensation of a power amplifier according to claim 9, wherein: In step S4, the effect integration result of the single-frequency signal and the distortion index of the multi-frequency signal are combined to determine whether to perform intermodulation distortion processing. The judgment rules are as follows: If the multi-frequency signal distortion index is greater than the distortion index threshold, it is judged as high distortion, and the feedback loop method is directly triggered to perform intermodulation distortion processing; if the multi-frequency signal distortion index is lower than the distortion index threshold, it is judged as low distortion; When the judgment result is low distortion, if the sub-frequency band is marked as a high-risk area, intermodulation distortion processing is performed; if the sub-frequency band is marked as a low-risk area, intermodulation distortion processing is not performed.

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