Broadband phase frequency compensation filter and construction method thereof, broadband phase frequency compensation method, medium and equipment

Abstract

The embodiment of the invention discloses a broadband phase frequency compensation filter, a construction method of the broadband phase frequency compensation filter, a broadband phase frequency compensation method, a medium and equipment, and relates to the technical field of communication. After a signal is compensated by the IIR all-pass phase frequency compensation filter, the fixed phase compensation module compensates a fixed phase deviation value between a compensated phase of the IIR all-pass phase frequency compensation filter and an actual phase characteristic of a system to be detected, and the fixed phase compensation module in an FFT-IFFT filtering form compensates a fixed phase value of each frequency point. The defect that a full-frequency-point fixed phase cannot be captured due to the fact that group delay is calculated in a traditional all-pass filter design is overcome, and therefore complete compensation is carried out on phase information of an acquisition system.

Description

Technical Field

[0001] The present application relates to the field of communication technology, and in particular to a broadband phase-frequency compensation filter and a construction method thereof, a broadband phase-frequency compensation method, a medium and a device. Background Art

[0002] In actual broadband acquisition systems, the irrational characteristics of RF circuits make it difficult for signals to achieve full-bandwidth amplitude-frequency response flatness and linear phase-frequency response conditions, so corresponding full-bandwidth system amplitude-frequency and phase-frequency response compensation is required. However, the system amplitude-frequency and phase-frequency response compensation based on a comprehensive filter group has high calculation cost and cannot solve the correction imbalance caused by correction accuracy. To solve the above correction imbalance problem, engineering implementation generally uses respective filters to complete amplitude-frequency and phase-frequency compensation.

[0003] In actual system applications, factors such as irrational system characteristics and impedance mismatch may cause fixed phase offsets in the entire frequency band. This fixed phase offset will cause the system to still have signal distortion after completing conventional phase-frequency compensation based on group delay. The reason is that in the process of group delay calculation, the phase difference of adjacent frequency points will offset this fixed phase offset, which ultimately leads to the inability of phase-frequency correction based on traditional all-pass IIR filters to capture this fixed phase offset, thereby failing to achieve complete compensation of phase information, resulting in the acquisition system's high-quality distortion-free signal acquisition not being effectively guaranteed. Summary of the invention

[0004] The main purpose of the present application is to provide a broadband phase-frequency compensation filter and a construction method thereof, a broadband phase-frequency compensation method, a medium and a device, aiming to solve the problem that the existing technology cannot achieve complete compensation of phase information.

[0005] To achieve the above objectives, the technical solutions adopted in the embodiments of the present application are as follows:

[0006] In a first aspect, an embodiment of the present application provides a broadband phase-frequency compensation filter, comprising:

[0007] A cascaded IIR all-pass phase-frequency compensation filter and a fixed phase compensation module, wherein the fixed phase compensation module is constructed based on the FFT-IFFT filtering form, and the fixed phase compensation module is used to compensate for the fixed phase deviation value between the phase compensated by the IIR all-pass phase-frequency compensation filter and the actual phase characteristic of the system to be measured.

[0008] In a second aspect, an embodiment of the present application provides a method for constructing a broadband phase-frequency compensation filter, which is used to construct the broadband phase-frequency compensation filter provided in the first aspect, comprising the following steps:

[0009] Obtaining a group delay estimation value of the system under test according to the phase estimation value of the system under test;

[0010] According to the estimated value of group delay, the coefficients of the IIR all-pass phase-frequency compensation filter are obtained and the IIR all-pass phase-frequency compensation filter is constructed;

[0011] According to the pole distribution of the IIR all-pass phase-frequency compensation filter, a phase compensation value is obtained;

[0012] Obtaining a fixed phase deviation value according to an actual phase value and a phase compensation value of the system to be tested;

[0013] Based on the fixed phase deviation value, a fixed phase compensation module based on FFT-IFFT filtering is constructed;

[0014] The IIR all-pass phase-frequency compensation filter and the fixed phase compensation module are cascaded to obtain a broadband phase-frequency compensation filter.

[0015] In a possible implementation manner of the second aspect, before obtaining the group delay estimation value of the system to be measured according to the phase estimation value of the system to be measured, the construction method further includes:

[0016] According to the target phase value and the phase-frequency response of the system to be measured, the phase estimation value of the system to be measured is obtained; wherein the target phase value is the phase value of the digital angular frequency after the Fourier transformation of the time-domain average data.

[0017] In a possible implementation manner of the second aspect, before obtaining a phase estimation value of the system to be measured according to the target phase value and the phase-frequency response of the system to be measured, the construction method further includes:

[0018] The time domain signal is subjected to average denoising processing to obtain the time domain average data.

[0019] In a possible implementation manner of the second aspect, before performing average denoising processing on the time domain signal to obtain time domain average data, the construction method further includes:

[0020] The data alignment algorithm based on peak search is used to align the collected data to obtain the time domain signal.

[0021] In a third aspect, an embodiment of the present application provides a broadband phase-frequency compensation method, using the broadband phase-frequency compensation filter provided in the first aspect above, comprising the following steps:

[0022] Get the original signal;

[0023] The original signal is input into the broadband phase-frequency compensation filter to obtain the target signal.

[0024] In a possible implementation manner of the third aspect, inputting the original signal into a broadband phase-frequency compensation filter to obtain a target signal includes:

[0025] The original signal is input into an IIR all-pass phase-frequency compensation filter of a broadband phase-frequency compensation filter for primary compensation to obtain a first output signal;

[0026] The first output signal is input into a fixed phase compensation module of a broadband phase-frequency compensation filter for secondary compensation to obtain a target signal.

[0027] In a possible implementation manner of the third aspect, the original signal is input into an IIR all-pass phase-frequency compensation filter of a broadband phase-frequency compensation filter for one-time compensation, and after obtaining a first output signal, the compensation method further includes:

[0028] According to the state of the fixed phase deviation value, the positive and negative signs of the zero-frequency signal are obtained;

[0029] The first output signal is input into a fixed phase compensation module of a broadband phase-frequency compensation filter for secondary compensation to obtain a target signal, including:

[0030] The first output signal is input into a fixed phase compensation module of a broadband phase-frequency compensation filter for secondary compensation, and a target signal is obtained based on the positive and negative signs of the zero-frequency signal.

[0031] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium storing a computer program. When the computer program is loaded and executed by a processor, it implements a method for constructing a broadband phase-frequency compensation filter as provided in any one of the second aspects above or a broadband phase-frequency compensation method as provided in any one of the third aspects above.

[0032] In a fifth aspect, an embodiment of the present application provides an electronic device, including a processor and a memory, wherein:

[0033] The memory is used to store computer programs;

[0034] The processor is used to load and execute a computer program so that the electronic device executes a method for constructing a broadband phase-frequency compensation filter as provided in any one of the second aspects or a broadband phase-frequency compensation method as provided in any one of the third aspects.

[0035] Compared with the prior art, the beneficial effects of this application are:

[0036] The embodiments of the present application propose a broadband phase-frequency compensation filter and a construction method thereof, a broadband phase-frequency compensation method, a medium and a device. The broadband phase-frequency compensation filter is composed of a cascaded IIR full-pass phase-frequency compensation filter and a fixed phase compensation module. After the signal is compensated by the IIR full-pass phase-frequency compensation filter, the fixed phase compensation module is used to compensate for the fixed phase deviation value between the phase compensated by the IIR full-pass phase-frequency compensation filter and the actual phase characteristic of the system to be measured. The fixed phase compensation module in the form of FFT-IFFT filtering is used to compensate for the fixed phase value of each frequency point, which makes up for the deficiency of the traditional all-pass filter design due to the inability to capture the fixed phase of all frequency points when calculating the group delay, thereby realizing complete compensation for the phase information of the acquisition system. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 A schematic diagram of the structure of a broadband phase-frequency compensation filter provided in an embodiment of the present application;

[0038] Figure 2 A schematic diagram of the structure of an electronic device of a hardware operating environment involved in an embodiment of the present application;

[0039] Figure 3 A schematic flow chart of a method for constructing a broadband phase-frequency compensation filter provided in an embodiment of the present application;

[0040] Figure 4 A schematic diagram of the relationship between group delays corresponding to various phase values ​​in the method for constructing a broadband phase-frequency compensation filter provided in an embodiment of the present application;

[0041] Figure 5 A schematic flow chart of a broadband phase-frequency compensation method provided in an embodiment of the present application;

[0042] Figure 6 A schematic diagram of a flow chart of a broadband phase-frequency compensation method provided in an embodiment of the present application in one implementation manner;

[0043] Figure 7 A schematic diagram showing the comparison between an unaligned time domain signal and an aligned time domain signal when testing the broadband phase-frequency compensation method provided in an embodiment of the present application;

[0044] Figure 8 It is a comparative schematic diagram of an uncompensated original signal, a signal compensated by a traditional IIR all-pass filter, and a signal compensated by a broadband phase-frequency compensation method provided in an embodiment of the present application;

[0045] Fig. 9 It is a schematic diagram comparing the signal before zero-frequency signal processing and the signal after zero-frequency signal processing by the broadband phase-frequency compensation method provided in the embodiment of the present application;

[0046] Fig.10A schematic diagram of a module of a device for constructing a broadband phase-frequency compensation filter provided in an embodiment of the present application;

[0047] Fig.11 A schematic diagram of a module of a broadband phase-frequency compensation device provided in an embodiment of the present application;

[0048] Markings in the figure: 101 - processor, 102 - communication bus, 103 - network interface, 104 - user interface, 105 - memory. DETAILED DESCRIPTION

[0049] It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0050] The current development trend of electronic systems is towards larger bandwidth, higher transmission rate, more information carrying, stronger anti-interference ability, etc., which requires test and measurement equipment to have higher sampling rate and larger analysis bandwidth. The improvement of high-speed broadband test and measurement equipment performance enables it to be directly applied to the distortion-free capture and time-domain waveform analysis of signals in the fields of broadband communication, broadband radar, broadband electronic countermeasures, etc. In actual broadband acquisition systems, the irrational characteristics of RF circuits will make it difficult for signals to achieve full-bandwidth amplitude-frequency response flatness and linear phase-frequency response conditions, so corresponding full-bandwidth system amplitude-frequency and phase-frequency response compensation is required.

[0051] However, the system amplitude-frequency and phase-frequency response compensation based on a comprehensive filter group has high computational cost and cannot solve the correction imbalance caused by the correction accuracy. Considering that the calculation of group delay in all-pass phase-frequency correction is the negative inverse of the phase to the digital angular frequency, when the sampling frequency points are dense, a small phase fluctuation between the frequency points will cause a large change in the group delay result, which is not conducive to the all-pass phase-frequency correction using the group delay curve fitting method. In contrast, the compensation accuracy of all-pass amplitude-frequency compensation for dense frequency points can be improved. In order to solve the above-mentioned correction imbalance problem, engineering implementation generally completes the amplitude-frequency and phase-frequency compensation by their own filters.

[0052] The all-pass amplitude-frequency correction is implemented by designing a linear phase FIR filter that does not affect the phase-frequency characteristics, while the all-pass phase-frequency correction is implemented by designing an all-pass IIR filter that does not affect the amplitude-frequency characteristics. In actual system applications, the conventional FIR filter designed based on the least squares method can meet the requirements of accurate all-pass amplitude-frequency compensation correction. For all-pass phase-frequency compensation, the design idea of ​​the all-pass IIR filter is to accurately fit the system group delay characteristics. Considering the irrational characteristics of the system, impedance mismatch and other factors that may cause a fixed phase offset in the entire frequency band, this fixed phase offset will cause the system to still have signal distortion after completing the conventional group delay-based phase-frequency compensation. The reason is that in the process of group delay calculation, the phase difference of adjacent frequency points will offset this fixed phase offset, which ultimately leads to the inability of the phase-frequency correction based on the traditional all-pass IIR filter to capture this fixed phase offset, thereby failing to achieve complete compensation of the phase information, resulting in the acquisition system's high-quality distortion-free signal acquisition not being effectively guaranteed.

[0053] For this purpose, as attached Figure 1 As shown, the embodiment of the present application provides a broadband phase-frequency compensation filter, comprising:

[0054] A cascaded IIR all-pass phase-frequency compensation filter and a fixed phase compensation module, wherein the fixed phase compensation module is constructed based on the FFT-IFFT filtering form, and the fixed phase compensation module is used to compensate for the fixed phase deviation value between the phase compensated by the IIR all-pass phase-frequency compensation filter and the actual phase characteristic of the system to be measured.

[0055] In this embodiment, a broadband phase-frequency compensation filter is formed by a cascaded IIR all-pass phase-frequency compensation filter and a fixed phase compensation module. After the signal is compensated by the IIR all-pass phase-frequency compensation filter, the fixed phase compensation module is used to compensate for the fixed phase deviation value between the phase compensated by the IIR all-pass phase-frequency compensation filter and the actual phase characteristic of the system to be measured. The fixed phase compensation module in the form of FFT-IFFT filtering is used to compensate for the fixed phase value of each frequency point, which makes up for the deficiency of the traditional all-pass filter design that cannot capture the fixed phase of all frequency points when calculating the group delay, thereby realizing complete compensation for the phase information of the acquisition system.

[0056] Refer to the attached Figure 2 , attached Figure 2This is a schematic diagram of the structure of an electronic device of the hardware operating environment involved in the embodiment of the present application. The electronic device may include: a processor 101, such as a central processing unit (CPU), a communication bus 102, a user interface 104, a network interface 103, and a memory 105. Among them, the communication bus 102 is used to realize the connection and communication between these components. The user interface 104 may include a display screen (Display), an input unit such as a keyboard (Keyboard), and the user interface 104 may also include a standard wired interface and a wireless interface. The network interface 103 may optionally include a standard wired interface and a wireless interface (such as a wireless fidelity (WIreless-FIdelity, WI-FI) interface). The memory 105 may optionally be a storage device independent of the aforementioned processor 101. The memory 105 may be a high-speed random access memory (RAM) memory, or it may be a stable non-volatile memory (NVM), such as at least one disk storage; the processor 101 may be a general-purpose processor, including a central processing unit, a network processor, etc., or it may be a digital signal processor, an application-specific integrated circuit, a field programmable gate array or other programmable logic device, a discrete gate or transistor logic device, or a discrete hardware component.

[0057] Those skilled in the art will appreciate that Figure 2 The structure shown in the figure does not constitute a limitation on the electronic device, and may include more or less components than shown in the figure, or combine certain components, or arrange the components differently.

[0058] As attached Figure 2 As shown, the memory 105 as a storage medium may include an operating system, a network communication module, a user interface module, and a construction device for a broadband phase-frequency compensation filter or a broadband phase-frequency compensation device.

[0059] In the attached Figure 2 In the electronic device shown, the network interface 103 is mainly used for data communication with a network server; the user interface 104 is mainly used for data interaction with a user; the processor 101 and the memory 105 in the present application can be set in the electronic device, and the electronic device calls the construction device of the broadband phase-frequency compensation filter or the broadband phase-frequency compensation device stored in the memory 105 through the processor 101, and executes the construction method of the broadband phase-frequency compensation filter or the broadband phase-frequency compensation method provided in the embodiment of the present application.

[0060] See attached Figure 3Based on the hardware device of the aforementioned embodiment, the embodiment of the present application provides a method for constructing a broadband phase-frequency compensation filter, which is used to construct a broadband phase-frequency compensation filter as provided in the embodiment of the present application, comprising the following steps:

[0061] S00: Obtaining a phase estimation value of the system under test according to a target phase value and a phase-frequency response of the system under test; wherein the target phase value is a phase value of a digital angular frequency after Fourier transformation of time-domain average data.

[0062] In the specific implementation process, the goal of the phase correction of the acquisition system is to obtain a linear phase-frequency response, and the corresponding group delay is a fixed delay value that does not change with frequency. For example, the group delay value of a certain frequency point represents the time delay experienced by the signal at that frequency point after passing through the system, and the same group delay value fixed in the entire frequency band represents the same time delay experienced by the frequency point signals of the entire frequency band after passing through the system. At this time, the time domain waveform of the signal is not distorted. According to the group delay calculation formula, the estimation of the phase-frequency response of the system in the full frequency band needs to consider the relative phase relationship between each frequency point rather than the independent phase value of a single frequency point. Therefore, the sinusoidal frequency sweep method used to obtain the full-pass amplitude-frequency response will no longer be applicable to the estimation of the system phase-frequency response. On the contrary, it is necessary to select a calibration excitation signal with a wide spectrum characteristic and a certain phase relationship between each frequency component.

[0063] Methods for estimating the phase-frequency response of broadband systems can be generally divided into two categories: the first category is to establish a reference system through a synchronization relationship, collect a calibration excitation signal with the reference system as a reference signal, and use the reference signal to find the relative phase relationship with the signal collected by the system under test as a phase reference value; the second category is to collect excitation signals of multiple harmonics with a known fixed phase relationship, such as periodic narrow pulse comb spectrum signals. Because the measurement accuracy of the first method is greatly affected by the synchronization accuracy, this application will use a periodic narrow pulse comb spectrum signal as an excitation signal to obtain the phase-frequency response of the system under test. Therefore, the phase-frequency response of the system under test can be expressed as:

[0064]

[0065] Among them, when the sampling rate is fixed, ω i is the digital angular frequency of the system’s i-th frequency point; The phase-frequency response value of the output signal collected by the system under test; The system inputs a periodic narrow pulse comb spectrum excitation signal at ω i Since the phase-frequency response of the above two signals is known, the phase-frequency characteristic of the system under test can be directly calculated by formula (1). is the time domain average data The digital angular frequency after Fourier transformation is ω i The phase value of Substituting into equation (1) we can get the phase estimation value of the system under test:

[0066] In one embodiment, before obtaining the phase estimation value of the system to be measured according to the target phase value and the phase-frequency response of the system to be measured, the construction method further includes:

[0067] The data alignment algorithm based on peak search is used to align the collected data to obtain the time domain signal;

[0068] The time domain signal is subjected to average denoising processing to obtain the time domain average data.

[0069] In the specific implementation process, in order to improve the estimation accuracy of the phase-frequency response of the system to be tested and avoid the group delay changes caused by small phase fluctuations caused by noise, this application eliminates the noise by averaging multiple acquired signals, and then calculates the system group delay. However, the averaging of multiple acquired signals requires the same trigger conditions. At the same time, the application of data alignment algorithm can avoid waveform jitter caused by unstable triggering. This application proposes a data alignment algorithm based on peak search to align the actual acquired data. Specifically:

[0070] Assume that the multiple acquisition signals to be aligned are X, and their size is N×N', where N is the number of time domain signal points acquired each time, and N' is the number of signal acquisition times. For the acquisition data X, first reorganize the acquisition signal size to K×MN', where K is defined as the number of sampling points of a single-cycle narrow pulse excitation signal, that is:

[0071]

[0072] f s is the system sampling frequency, f c is the fundamental frequency of the narrow pulse excitation signal; M is defined as the number of multiple narrow pulse excitation signal cycles contained in each sampling of N points, that is:

[0073]

[0074] floor(·) is a rounding operation. Here, the number of points remaining after each acquisition signal is rounded down is discarded, that is, N-MK. Subsequently, each column of data is interpolated, and finally a reorganized data matrix X' with a size of K'×MN' is obtained, where K' is the number of single-cycle narrow pulse excitation signal data points after interpolation. The second step is to search for the peak value of each column of data in the reorganized matrix X' to find its minimum value and its coordinate index value, that is, Here j represents the jth column data in the matrix X'. Sorting is performed, where the column data corresponding to the minimum index value is used as a reference, and the other column data are aligned to it. Let the minimum index value and its corresponding column be The number of points that need to be dropped on the left side of the j-th column data is:

[0075]

[0076] According to the above delay points Data alignment must meet the following requirements:

[0077]

[0078] in, is the jth column of unaligned data; The jth column is the aligned data; The aligned time domain signal is averaged and denoised to obtain:

[0079]

[0080] S10: Obtaining a group delay estimation value of the system under test according to the phase estimation value of the system under test.

[0081] In the specific implementation process, the group delay of the system to be tested can be obtained according to the following formula:

[0082]

[0083] S20: According to the group delay estimation value, obtain the IIR all-pass phase-frequency compensation filter coefficient and construct the IIR all-pass phase-frequency compensation filter.

[0084] In the specific implementation process, after obtaining the system group delay characteristics, the system group delay can be fitted by designing an IIR all-pass filter to compensate for the phase distortion in the passband. The system function of the second-order cascade form of the IIR all-pass filter is defined as:

[0085]

[0086] Among them, r p and θ p are the modulus and phase angle of the pth second-order section pole, respectively, and P is the order of the all-pass filter. According to the definition of the second-order section in formula (8), the relationship between the group delay and the pole of a single second-order section can be:

[0087]

[0088] At the same time, the integral of the group delay of a single second-order section in [0,π] is always:

[0089]

[0090] From (9) and (10), we can see that the value of group delay varies with the pole modulus r p At this time, its integral curve will become narrower and narrower, and more concentrated at ω=θp Therefore, the target group delay can be cut into P intervals with an area of ​​2π by a graphical method, and the group delay value of the system to be measured can be fitted by adjusting the modulus length and phase angle of each second-order section pole of the all-pass filter. The final all-pass filter coefficients are the modulus length and phase angle of each second-order section pole, such as (r p ,θ p ), where p = 1, ..., P / 2.

[0091] S30: Obtaining a phase compensation value according to the pole distribution of the IIR all-pass phase-frequency compensation filter.

[0092] S40: Obtaining a fixed phase deviation value according to an actual phase value and a phase compensation value of the system to be tested.

[0093] In the specific implementation process, according to the pole distribution of the all-pass filter, the actual phase compensation value of each frequency point can be calculated using the following formula:

[0094]

[0095] As mentioned in the previous step, the graphical method for generating all-pass filter coefficients requires cutting the target group delay into P intervals with an area of ​​2π. To ensure the causality of the target group delay, Compared with the actual phase of the system under test, the inverted value is taken, such as There will be D extra -P-δ DUT The linear delay of extra is an additional delay parameter used to control the target group delay area to be exactly 2πP, δ DUT is a small linear delay error. The linear delay D added to generate the filter coefficients is removed. extra -P-δ DUT The difference between the actual phase value of the system and the phase deviation that cannot be compensated by the all-pass filter is the fixed phase deviation value. Figure 4 The relationship between the group delays corresponding to each phase value is shown in . Based on the above analysis, minus Remove linear delay D extra -P-δ DUT The value after averaging can be obtained to obtain the fixed phase deviation between the phase compensated by the all-pass filter and the actual phase characteristic of the system to be measured, that is:

[0096]

[0097] S50: Based on the fixed phase deviation value, a fixed phase compensation module based on FFT-IFFT filtering is constructed.

[0098] S60: cascade the IIR all-pass phase-frequency compensation filter and the fixed phase compensation module to obtain a broadband phase-frequency compensation filter.

[0099] In the specific implementation process, since the main purpose of the all-pass filter is to compensate for the system group delay, according to the group delay calculation formula, fixed phase values ​​such as (12) that do not change with frequency will be eliminated due to differential subtraction during the group delay formula calculation process, which ultimately leads to the inability of the all-pass filter to capture this fixed phase value and compensate for it. To this end, the system can compensate for the fixed phase value for each frequency point through the cascaded FFT-IFFT filtering form. At the same time, in order to solve the problems of complex calculations caused by large-point Fourier transforms and spectrum leakage caused by non-integer multiple periods, the system logic implements frequency domain FFT-IFFT fixed phase value compensation based on the concept of overlapping frames. By introducing multiple additional and identical filtering modules and dividing large segments of data into several small segments as required, each module filters data frames with different starting positions. Since the data frames processed by each filtering module have overlapping parts, the system selects the data frames processed by different modules according to certain rules, so as to finally obtain filtered data without spectrum leakage and with controllable calculation amount. Finally, the constructed IIR all-pass phase-frequency compensation filter and the fixed phase compensation module are cascaded as shown in the attached figure. Figure 1 The broadband phase-frequency compensation filter shown.

[0100] The beneficial effects of this embodiment can be referred to the above embodiments, which will not be described in detail here. Figure 5 Based on the same inventive concept as in the above-mentioned embodiment, the embodiment of the present application further provides a broadband phase-frequency compensation method, using a broadband phase-frequency compensation filter as provided in the embodiment of the present application, comprising the following steps:

[0101] S70: Obtaining an original signal.

[0102] S80: Input the original signal into the broadband phase-frequency compensation filter to obtain the target signal.

[0103] In the specific implementation process, as shown in the attached Figure 1 As shown, the original signal is the signal to be calibrated and compensated. The calibration signal is input into the filter, first compensated by the IIR full-pass phase-frequency compensation filter, and then compensated by the fixed phase compensation module. Finally, the calibration signal is output to obtain a signal with complete compensation of phase information. That is, the original signal is input into the broadband phase-frequency compensation filter to obtain the target signal, including:

[0104] The original signal is input into an IIR all-pass phase-frequency compensation filter of a broadband phase-frequency compensation filter for primary compensation to obtain a first output signal;

[0105] The first output signal is input into a fixed phase compensation module of a broadband phase-frequency compensation filter for secondary compensation to obtain a target signal.

[0106] The above steps are performed through the system group delay estimation module, the IIR all-pass phase-frequency compensation filter coefficient generation module, the fixed phase offset value calculation module and the FFT-IFFT-based fixed phase compensation module to estimate the phase characteristics of each frequency point of the system, calculate the system group delay, and generate the all-pass filter coefficient to infer the system fixed phase offset information, and then use the FFT-IFFT operation to perform conventional IIR phase compensation and then fixed phase offset compensation on the system, so as to achieve the purpose of distortion-free correction of the final phase of the system.

[0107] In one embodiment, the original signal is input into an IIR all-pass phase-frequency compensation filter of a broadband phase-frequency compensation filter for a compensation, and after obtaining a first output signal, the compensation method further comprises:

[0108] According to the state of the fixed phase deviation value, the positive and negative signs of the zero-frequency signal are obtained.

[0109] In the specific implementation process, in order not to change the size of the DC signal, this application will not perform a fixed phase compensation operation on the zero-frequency signal, but its sign should change with the sign of the result of multiplying other frequency points with the fixed phase value. Otherwise, due to the introduction of overlapping frames, the compensated signal will have a discontinuity phenomenon. To achieve the above operation, as shown in the attached Figure 6 As shown in the figure, first assume that the time domain signal output after IIR all-pass filter compensation is y(n), perform FFT Fourier transform on y(n) to obtain signal Y(jω), and multiply it with the fixed phase deviation in the frequency domain. Then, determine whether the fixed phase compensation value will change the sign of the multiplied frequency domain signal Y'(jω), that is, determine Is it less than zero? If it changes, it means it is less than zero, and the sign of the zero-frequency signal Y′(0) needs to change at the same time. After frequency domain compensation, the signal will be subjected to IFFT Fourier inverse transform to restore the time domain signal. The final z(n) is the calibration and compensation data, that is, the target signal. Fig. 9 As shown, it is a comparative schematic diagram of the signal before zero-frequency signal processing and after zero-frequency signal processing by the broadband phase-frequency compensation method provided in the embodiment of the present application. The signal fault phenomenon is solved, thereby completely restoring the compensated signal.

[0110] Based on the above steps, the first output signal is input into the fixed phase compensation module of the broadband phase-frequency compensation filter for secondary compensation to obtain the target signal, including:

[0111] The first output signal is input into a fixed phase compensation module of a broadband phase-frequency compensation filter for secondary compensation, and a target signal is obtained based on the positive and negative signs of the zero-frequency signal.

[0112] Refer to the attached Figure 7, a schematic diagram showing the comparison of the unaligned time domain signal and the aligned time domain signal when testing the broadband phase-frequency compensation method provided in the embodiment of the present application. Compared with the traditional frequency domain signal alignment method, the time domain signal alignment method based on peak search used in the present application in calculating the system group delay is better in the waveform distorted signal caused by the harmonic component. The fast edge signal is collected multiple times based on the narrow pulse fast edge signal generator. The upper sub-graph is an unaligned single-cycle narrow pulse time domain signal, and its signal fluctuation range is about 10 sampling points. After the time domain waveform is aligned by the time domain waveform alignment algorithm of the present application, the signal fluctuation of the lower sub-graph is reduced to about 3 sampling points. This fluctuation is mostly caused by noise. After averaging the signal, the noise can be weakened, so that the phase-frequency characteristics of the system can be accurately extracted.

[0113] Refer to the attached Figure 8 , which is a comparative schematic diagram of the uncompensated original signal, the signal after compensation by the traditional IIR all-pass filter, and the signal after compensation by the broadband phase-frequency compensation method provided in the embodiment of the present application. The upper sub-figure is the phase-uncompensated original square wave signal, and this signal has severe phase distortion. The middle sub-figure is the signal after compensation by the traditional IIR all-pass filter, and its signal distortion degree has not been improved. The lower sub-figure is the signal after the cascaded IIR all-pass filter compensation and fixed phase value compensation design of the present application, and its signal distortion is greatly improved, thereby proving the effectiveness of the compensation method of the present application. It is worth noting that the design concept of the traditional IIR all-pass filter is group delay compensation. Due to its own characteristics, it is impossible to compensate for the fixed phase value introduced by the hardware defects of the system itself. For this reason, the FFT-IFFT module provided by the present application needs to be cascaded to perform complete phase compensation of the system.

[0114] Refer to the attached Fig.10 Based on the same inventive concept as in the above-mentioned embodiment, the embodiment of the present application further provides a device for constructing a broadband phase-frequency compensation filter, comprising:

[0115] A group delay estimation module, used to obtain a group delay estimation value of the system under test according to a phase estimation value of the system under test;

[0116] The first construction module is used to obtain the IIR all-pass phase-frequency compensation filter coefficients and construct the IIR all-pass phase-frequency compensation filter according to the group delay estimation value;

[0117] A phase compensation obtaining module, used for obtaining a phase compensation value according to the pole distribution of the IIR all-pass phase-frequency compensation filter;

[0118] A fixed phase deviation obtaining module is used to obtain a fixed phase deviation value according to an actual phase value and a phase compensation value of the system to be tested;

[0119] The second building module is used to build a fixed phase compensation module based on the FFT-IFFT filtering form based on the fixed phase deviation value;

[0120] The target building block is used to cascade the IIR all-pass phase-frequency compensation filter and the fixed phase compensation module to obtain a broadband phase-frequency compensation filter.

[0121] Refer to the attached Fig.11 Based on the same inventive concept as in the above-mentioned embodiment, the embodiment of the present application further provides a broadband phase-frequency compensation device, comprising:

[0122] An acquisition module, used for acquiring the original signal;

[0123] The compensation module is used to input the original signal into the broadband phase-frequency compensation filter to obtain the target signal.

[0124] Those skilled in the art should understand that the division of the various modules in the embodiment is merely a division of logical functions, and in actual application, all or part of them can be integrated into one or more actual carriers, and these modules can be implemented entirely in the form of software called by a processing unit, or entirely in the form of hardware, or in the form of a combination of software and hardware. It should be noted that the modules in the construction device of the broadband phase-frequency compensation filter and the broadband phase-frequency compensation device in this embodiment correspond one-to-one to the steps in the construction method of the broadband phase-frequency compensation filter and the broadband phase-frequency compensation method in the aforementioned embodiment. Therefore, the specific implementation method of this embodiment can refer to the aforementioned implementation method, which will not be repeated here.

[0125] Based on the same inventive concept as in the aforementioned embodiments, an embodiment of the present application further provides a computer-readable storage medium storing a computer program. When the computer program is loaded and executed by a processor, a method for constructing a broadband phase-frequency compensation filter or a broadband phase-frequency compensation method as provided in the embodiments of the present application is implemented.

[0126] Based on the same inventive concept as in the above-mentioned embodiment, an embodiment of the present application further provides an electronic device, including a processor and a memory, wherein:

[0127] The memory is used to store computer programs;

[0128] The processor is used to load and execute a computer program so that the electronic device executes a method for constructing a broadband phase-frequency compensation filter or a broadband phase-frequency compensation method as provided in the embodiments of the present application.

[0129] In some embodiments, the computer readable storage medium may be a memory such as FRAM, ROM, PROM, EPROM, EEPROM, flash memory, magnetic surface memory, optical disk, or CD-ROM; or various devices including one or any combination of the above memories. The computer may be various computing devices including intelligent terminals and servers.

[0130] In some embodiments, executable instructions may be in the form of a program, software, software module, script or code, written in any form of programming language (including compiled or interpreted languages, or declarative or procedural languages), and may be deployed in any form, including as a stand-alone program or as a module, component, subroutine or other unit suitable for use in a computing environment.

[0131] As an example, executable instructions may, but need not, correspond to a file in a file system, may be stored as part of a file that stores other programs or data, such as in one or more scripts in a HyperText Markup Language (HTML) document, in a single file dedicated to the program in question, or in multiple coordinated files (e.g., files storing one or more modules, subroutines, or code portions).

[0132] By way of example, executable instructions may be deployed to be executed on one computing device, or on multiple computing devices located at one site, or on multiple computing devices distributed across multiple sites and interconnected by a communication network.

[0133] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or system including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or system. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or system including the element.

[0134] The serial numbers of the above-mentioned embodiments of the present application are for description only and do not represent the advantages or disadvantages of the embodiments.

[0135] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present application, or the part that contributes to the prior art, can be embodied in the form of a software product, which is stored in a storage medium (such as a read-only memory / random access memory, a magnetic disk, or an optical disk), and includes a number of instructions for enabling a multimedia terminal device (which can be a mobile phone, a computer, a television receiver, or a network device, etc.) to execute the methods described in each embodiment of the present application.

[0136] In summary, the present application provides a broadband phase-frequency compensation filter and a construction method thereof, a broadband phase-frequency compensation method, a medium and a device. The broadband phase-frequency compensation filter is composed of a cascaded IIR full-pass phase-frequency compensation filter and a fixed phase compensation module. After the signal is compensated by the IIR full-pass phase-frequency compensation filter, the fixed phase compensation module is used to compensate for the fixed phase deviation value between the compensated phase of the IIR full-pass phase-frequency compensation filter and the actual phase characteristic of the system to be measured. The fixed phase compensation module in the form of FFT-IFFT filtering is used to compensate for the fixed phase value of each frequency point, which makes up for the deficiency of the traditional all-pass filter design due to the inability to capture the fixed phase of all frequency points when calculating the group delay, thereby realizing complete compensation for the phase information of the acquisition system.

[0137] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A broadband phase-frequency compensation filter, characterized in that: include: A cascaded IIR all-pass phase-frequency compensation filter and a fixed phase compensation module, wherein the fixed phase compensation module is constructed based on the FFT-IFFT filtering form, and the fixed phase compensation module is used to compensate for the fixed phase deviation value between the phase compensated by the IIR all-pass phase-frequency compensation filter and the actual phase characteristic of the system to be measured.

2. A method for constructing a broadband phase-frequency compensation filter, characterized in that: The method for constructing the broadband phase-frequency compensation filter as claimed in claim 1 comprises the following steps: Obtaining a group delay estimation value of the system under test according to the phase estimation value of the system under test; According to the group delay estimation value, obtaining IIR all-pass phase-frequency compensation filter coefficients and constructing an IIR all-pass phase-frequency compensation filter; Obtaining a phase compensation value according to the pole distribution of the IIR all-pass phase-frequency compensation filter; Obtaining a fixed phase deviation value according to the actual phase value of the system to be tested and the phase compensation value; Based on the fixed phase deviation value, a fixed phase compensation module based on FFT-IFFT filtering is constructed; The IIR all-pass phase-frequency compensation filter and the fixed phase compensation module are cascaded to obtain a broadband phase-frequency compensation filter.

3. The method for constructing a broadband phase-frequency compensation filter according to claim 2, characterized in that: Before obtaining the group delay estimation value of the system to be measured according to the phase estimation value of the system to be measured, the construction method further includes: According to the target phase value and the phase-frequency response of the system to be measured, a phase estimation value of the system to be measured is obtained; wherein the target phase value is the phase value of the digital angular frequency after the Fourier transformation of the time-domain average data.

4. The method for constructing a broadband phase-frequency compensation filter according to claim 3, characterized in that: Before obtaining the phase estimation value of the system to be measured according to the target phase value and the phase-frequency response of the system to be measured, the construction method further includes: The time domain signal is subjected to average denoising processing to obtain the time domain average data.

5. The method for constructing a broadband phase-frequency compensation filter according to claim 4, characterized in that: Before performing the average denoising process on the time domain signal to obtain the time domain average data, the construction method further includes: The collected data is aligned using a data alignment algorithm based on peak search to obtain the time domain signal.

6. A broadband phase-frequency compensation method, characterized in that: The broadband phase-frequency compensation filter as claimed in claim 1 comprises the following steps: Get the original signal; The original signal is input into a broadband phase-frequency compensation filter to obtain a target signal.

7. The broadband phase-frequency compensation method according to claim 6, characterized in that: The step of inputting the original signal into a broadband phase-frequency compensation filter to obtain a target signal comprises: Inputting the original signal into an IIR all-pass phase-frequency compensation filter of a broadband phase-frequency compensation filter for primary compensation to obtain a first output signal; The first output signal is input into the fixed phase compensation module of the broadband phase-frequency compensation filter for secondary compensation to obtain a target signal.

8. The broadband phase-frequency compensation method according to claim 7, characterized in that: After inputting the original signal into an IIR all-pass phase-frequency compensation filter of a broadband phase-frequency compensation filter for primary compensation and obtaining a first output signal, the compensation method further comprises: According to the state of the fixed phase deviation value, the positive and negative signs of the zero-frequency signal are obtained; The step of inputting the first output signal into the fixed phase compensation module of the broadband phase-frequency compensation filter for secondary compensation to obtain a target signal comprises: The first output signal is input into the fixed phase compensation module of the broadband phase-frequency compensation filter for secondary compensation, and a target signal is obtained based on the positive and negative signs of the zero-frequency signal.

9. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is loaded and executed by the processor, the method for constructing a broadband phase-frequency compensation filter as described in any one of claims 2 to 5 or the broadband phase-frequency compensation method as described in any one of claims 6 to 8 is implemented.

10. An electronic device, characterized in that: comprising a processor and a memory, wherein: The memory is used to store computer programs; The processor is used to load and execute the computer program so that the electronic device executes the method for constructing a broadband phase-frequency compensation filter as described in any one of claims 2 to 5 or the broadband phase-frequency compensation method as described in any one of claims 6 to 8.

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