Frequency hopping parameter tuning optimization method for frequency hopping filter

Abstract

The invention discloses a frequency hopping parameter tuning optimization method for a frequency hopping filter, and relates to the technical field of filters, and the method comprises the steps: S1, respectively recording all frequency hopping and frequency leakage of a frequency hopping implementation strategy as a first sequence point and a second sequence point on a time axis; s2, screening out the second sequence points of which the leakage parameter values reach a reference threshold value, marking the second sequence points as interference sequence points, and marking the first sequence points closest to the interference sequence points as modulation sequence points; s3, performing gradual transition correction on frequency hopping conversion between each modulation sequence point and the adjacent first sequence point by using an exponential gradual transition method; and S4, updating the corrected first sequence point to the frequency hopping implementation strategy. By setting the reference threshold value to screen the leakage points and dynamically correcting the modulation sequence points and the frequency hopping parameters, the method has the beneficial effects of remarkably improving the frequency hopping working stability and low interference performance of the frequency hopping filter.

Description

Technical Field

[0001] The invention relates to the technical field of filters, and in particular to a frequency hopping parameter tuning optimization method for a frequency hopping filter. Background Art

[0002] Frequency hopping technology is a wireless communication technology that transmits signals by quickly switching between multiple frequencies. This technology is widely used in wireless communications, military, Bluetooth, satellite communications and other fields, and has the advantages of anti-interference, strong confidentiality, and improved spectrum utilization. The main function of the frequency hopping filter is to isolate the frequency band occupied by the signal from other interfering signals in adjacent frequency bands. Since the frequency of the frequency hopping signal changes rapidly and irregularly, the filter needs to have strong frequency selectivity to effectively filter out unnecessary frequency components to ensure that the signal in the target frequency band can be transmitted clearly.

[0003] In the existing frequency hopping communication process, there is often adjacent frequency interference due to transient leakage. Adjacent frequency interference refers to the failure of the filter to completely isolate the unwanted signal, causing the frequency components of the signal to leak into the adjacent frequency band, thereby affecting the signals in other frequency bands. If the frequency hopping rate is too fast, the transition between frequency switching is not smooth, and the frequency hopping signal may produce strong transient leakage at the moment of frequency switching. This transient leakage will cause adjacent frequency interference. Even for a frequency hopping filter with high precision that can effectively reduce transient leakage, when the frequency jumps too fast, the non-smooth transition of the frequency hopping signal during the frequency switching process will still cause transient leakage; the intensity of transient leakage is directly related to the intensity of the switching frequency. When the frequency hopping rate is too high, the frequency switching process may be too hasty and it is difficult to avoid strong transient fluctuations. At present, the accuracy of adjacent frequency interference correction for frequency hopping filters in the existing technology is poor, and it mainly relies on the adjustment of filter parameters based on a large number of correction samples, which makes the work cost of adjacent frequency interference parameter correction high and the accuracy low. Summary of the invention

[0004] The present invention provides a frequency hopping parameter tuning optimization method for a frequency hopping filter, which solves the problem that the adjacent frequency interference correction accuracy caused by transient leakage in the process of high-speed frequency hopping of the existing frequency hopping filter is low.

[0005] The present invention is achieved through the following technical solutions: A frequency hopping parameter tuning optimization method for a frequency hopping filter, the method comprising: Step S1: the target filter performs frequency hopping according to a preset frequency hopping implementation strategy and keeps monitoring, and the frequency hopping records and leakage parameter values ​​of all frequency leakages obtained by monitoring are recorded as the first sequence point and the second sequence point on the time axis respectively; Step S2: Record the leakage parameter value of the frequency leakage and set a reference threshold, screen out the second sequence point whose leakage parameter value reaches the reference threshold and mark it as an interference sequence point, and mark the first sequence point closest to the interference sequence point as a modulation sequence point; Step S3: recording the frequency hopping filter parameters of the target filter corresponding to the occurrence of all first sequence points, and using an exponential gradual transition method to perform a gradual transition correction on the frequency hopping transformation between each modulation sequence point and its adjacent first sequence point; Step S4: re-label all the corrected modulation sequence points as first sequence points, and correct the frequency hopping filter parameters of the target filter at the corresponding first sequence points according to the frequency values ​​of the corrected first sequence points, and update the time positions of the corrected first sequence points and the corresponding frequency hopping filter parameters to the frequency hopping implementation strategy.

[0006] Furthermore, the leakage parameter value includes a frequency leakage intensity value and a transient leakage waveform amplitude; the setting content of the reference threshold is that the frequency leakage intensity value and the transient leakage waveform amplitude correspond to a first reference value and a second reference value respectively; when at least one leakage parameter value among the frequency leakage intensity value and the transient leakage waveform amplitude recorded at the first sequence point reaches the corresponding reference threshold, the first sequence point is marked as an interference sequence point.

[0007] Furthermore, the contents of the exponential gradual transition method include: The target transition interval is set with the modulation sequence point and the adjacent first sequence point as endpoints on the time axis, and the frequency value of the frequency hopping of the target filter at the corresponding sequence point is marked in the corresponding time sequence at the endpoint of the target transition interval, and the frequency value of the frequency hopping is represented as the initial frequency value f0 and the frequency hopping frequency value f in sequence along the chronological position. t , where t represents a time point on the time axis; let the target frequency change corresponding to each target transition interval in the preset frequency hopping implementation strategy be expressed as Δf, let the transition time constant be expressed as τ, Then the frequency hopping frequency value f in the target transition interval is t It is expressed as: .

[0008] Furthermore, the frequency hopping range of the target filter is decomposed into a number of working frequency bands, and a piecewise exponential gradual transition function is used to perform a smooth gradual transition on the frequency hopping transformation of multiple working frequency bands between the modulation sequence point and the adjacent first sequence point.

[0009] Furthermore, a PID control method is used to dynamically adjust the transition time constant according to the difference between the target frequency and the current frequency, which includes: marking the actual frequency change of each target transition interval before correction, and calculating the frequency difference between the target frequency change and the actual frequency change; setting the error accumulation value of the target filter from running to the current moment and the error change rate value of the target filter frequency at the current moment, and using the gain coefficient of the PID control method as the weight value to perform weighted summation on the frequency difference, the error accumulation value and the error change rate value, and setting the summation result as the transition time constant; Assume that the actual frequency change is expressed as Δf p , let the frequency difference between the target frequency change and the actual frequency change be expressed as E, and the gain coefficient corresponding to the frequency difference is the proportional gain coefficient, which is used to control the influence of the frequency difference on the time constant, wherein the calculation form of the frequency difference E is expressed as: E(t)=|Δf-Δf p |.

[0010] Furthermore, the error accumulation value is expressed as , and the gain coefficient corresponding to the error accumulation value is an integral gain coefficient, which is used to control the influence of error accumulation on the time constant.

[0011] Further, the error change rate value is expressed as , and the gain coefficient corresponding to the error change rate value is a differential gain coefficient, which is used to control the influence of the error change rate on the time constant.

[0012] Furthermore, the first reference value is set to the mean of all frequency leakage intensity values ​​plus twice the standard deviation of the frequency leakage intensity values, and the second reference value is set to the mean of all transient leakage waveform amplitudes plus once the standard deviation of the transient leakage waveform amplitude.

[0013] Furthermore, the frequency leakage intensity value is obtained by calculating the difference in power spectrum density between the target frequency band and the adjacent frequency band; the transient leakage waveform amplitude is obtained by calculating the maximum overshoot amplitude value after frequency switching and the transition response of the target filter.

[0014] Furthermore, let the maximum overshoot amplitude be denoted as δ, let the transient response of the target filter be denoted as H(t), and let the output value of the target filter in a steady state be denoted as H final , then the maximum overshoot amplitude value calculation formula is expressed as: .

[0015] Compared with the prior art, the present invention sets a reference threshold to screen leakage points, uses an exponential gradient transition method to correct changes between frequency hopping points, avoids excessively fast or sudden frequency hopping, and dynamically corrects modulation sequence points and frequency hopping parameters to update the working parameters of the filter in real time, so that it always maintains the best state during high-speed frequency hopping, thereby effectively reducing adjacent frequency interference caused by transient leakage. It has the advantages of significantly improving the interference correction accuracy of the frequency hopping filter under high-speed frequency hopping and ensuring the stable frequency hopping operation and low-interference performance of the frequency hopping filter. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, constitute a part of this application, and do not constitute a limitation of the embodiments of the present invention. In the drawings: Figure 1 It is a flowchart of the present invention. DETAILED DESCRIPTION

[0017] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with embodiments and drawings. The exemplary embodiments of the present invention and their description are only used to explain the present invention and are not intended to limit the present invention. Example

[0018] like Figure 1 As shown, this embodiment is a frequency hopping parameter tuning optimization method for a frequency hopping filter, the method comprising: Step S1: the target filter performs frequency hopping according to a preset frequency hopping implementation strategy and keeps monitoring, and the frequency hopping records and leakage parameter values ​​of all frequency leakages obtained by monitoring are recorded as the first sequence point and the second sequence point on the time axis respectively; Step S2: Record the leakage parameter value of the frequency leakage and set a reference threshold, screen out the second sequence point whose leakage parameter value reaches the reference threshold and mark it as an interference sequence point, and mark the first sequence point closest to the interference sequence point as a modulation sequence point; Step S3: recording the frequency hopping filter parameters of the target filter corresponding to the occurrence of all first sequence points, and using an exponential gradual transition method to perform a gradual transition correction on the frequency hopping transformation between each modulation sequence point and its adjacent first sequence point; Step S4: re-label all the corrected modulation sequence points as first sequence points, and correct the frequency hopping filter parameters of the target filter at the corresponding first sequence points according to the frequency values ​​of the corrected first sequence points, and update the time positions of the corrected first sequence points and the corresponding frequency hopping filter parameters to the frequency hopping implementation strategy.

[0019] The design of frequency hopping filters usually requires fast switching between different frequencies. However, during this hopping process, due to the limitations of the physical system, such as bandwidth limitation, response speed, etc., the filter will have transient effects when hopping, causing the signal energy to leak into other frequency areas, which is the so-called "frequency leakage". Frequency leakage is mainly caused by the transient response of the filter or signal during the frequency hopping process, which manifests as the unintentional propagation of signal energy into the frequency band that should be isolated. The preset frequency hopping implementation strategy of the target filter refers to a set of rules or schemes determined and set in advance when designing and operating the target filter, which indicates the behavior of the filter in the frequency hopping process; the frequency hopping implementation strategy covers the frequency selection, frequency switching timing, frequency hopping amplitude, frequency hopping rate and other aspects of the filter's frequency hopping process. The frequency leakage refers to the signal frequency expansion or overflow to the adjacent frequency range during the frequency hopping process of the filter, causing unnecessary interference. The leakage parameter value can be a numerical indicator describing the leakage intensity, frequency range or leakage rate. For example, in some implementation processes, it can be counted as the amplitude of the leakage signal, the frequency offset, the time characteristics of the leakage frequency, etc. The frequency hopping record refers to the frequency value, time, and corresponding filter state of each hopping of the target filter during the high-speed frequency hopping process. The first sequence point refers to marking all frequency hopping events on the time axis (i.e., the time and frequency value of the filter hopping frequency). The time of each frequency hopping and the hopping frequency form a "time-frequency" pair, and these points form the first sequence on the time axis. The second sequence point refers to marking all the times when frequency leakage occurs and the degree of leakage on the time axis, that is, each leakage event corresponds to a "time-leakage parameter value" pair, and these points form the second sequence on the time axis.

[0020] More importantly, in order to effectively screen out the leakage points that significantly interfere with the system, a reference threshold value needs to be set. The reference threshold value represents the maximum tolerance range of the intensity of the leakage signal or the frequency offset, which belongs to a preset standard. When the frequency leakage degree reaches the reference threshold value standard, it is considered that the frequency leakage has an impact on the system and must be intervened and corrected. At this time, it is determined that the current corresponding time point is an interference point, and the interference point is marked as an "interference sequence point", indicating that it is a key point that needs to be corrected, because the frequency leakage generated by it may interfere with the signals of adjacent frequency bands. The reference threshold value can be set based on historical experience or historical data mean, or it can be set by experimental simulation. After the interference sequence point is determined, the frequency hopping sequence point adjacent to the interference point is found, that is, the first sequence point that is about to perform frequency hopping or has just completed frequency hopping. These points are the frequency hopping signal points closest to the interference point and belong to the "modulation sequence points" that need to be adjusted the most. By adjusting the frequency hopping parameters of these modulation points, the adjacent frequency interference caused by frequency leakage can be alleviated or eliminated. The frequency hopping filter parameters of the target filter refer to the parameters that need to be adjusted or controlled by a specific filter during the frequency hopping process, which are used to ensure that the conversion of the filter between different frequencies can work stably and effectively. In the specific implementation process, the frequency hopping filter parameters of the target filter may include relevant parameters such as center frequency, bandwidth gain, filter order and harmonic phase response. The exponential gradient transition method is a mathematical method, which is usually used for smooth transition in the process of change to correct sudden changes or drastic changes. If the frequency needs to change from one value to another, a direct jump may cause instability or interference of the signal. Through the exponential gradient transition, the frequency change can be gradually slowed down within a certain period of time, thereby reducing the adverse effects of sudden changes. In the frequency hopping filter, when the frequency hopping parameters change, the exponential gradient transition will make the frequency change relatively fast at the beginning, and then gradually slow down over time, and finally achieve a smooth transition, avoiding drastic jumps in the frequency during the change process, thereby reducing transient effects and frequency leakage in the frequency hopping process, thereby reducing interference and errors. According to the corrected first sequence point frequency value, the filter parameters are readjusted to adapt to the corrected frequency state, that is, the filter operating frequency, gain, bandwidth and other parameters are readjusted according to the corrected first sequence point to ensure that the filter can effectively filter out interference at the new frequency point while maintaining high performance. After the frequency hopping parameters are optimized and corrected, the corrected first sequence point and the corresponding filter parameters are updated to the frequency hopping implementation strategy in a timely manner to ensure that the filter can perform frequency hopping operation according to the optimized parameters in actual work.

[0021] Further, as a feasible implementation method, the leakage parameter value includes a frequency leakage intensity value and a transient leakage waveform amplitude; the setting content of the reference threshold is that the frequency leakage intensity value and the transient leakage waveform amplitude correspond to a first reference value and a second reference value respectively; when at least one leakage parameter value among the frequency leakage intensity value and the transient leakage waveform amplitude recorded at the first sequence point reaches the corresponding reference threshold, the first sequence point is marked as an interference sequence point.

[0022] The frequency leakage intensity value refers to the amplitude or energy of the leakage signal. The larger the frequency leakage intensity value, the stronger the energy leaked to the adjacent frequency range, which may interfere with the surrounding signals. In the prior art, it can usually be directly obtained through a spectrum analyzer. The amplitude of the frequency leakage signal or the energy of the leakage signal is usually expressed in decibels dB. The transient leakage waveform amplitude refers to the amplitude of the instantaneous signal leakage caused by the transient change of frequency or signal during signal processing or frequency hopping. In a frequency hopping system, the frequency change is usually gradual, but if the frequency changes too fast or not smooth, it may cause discontinuous waveforms or short-term drastic changes in the spectrum. This drastic change is called a transient effect; the instantaneous peak value (i.e., the highest amplitude point) that appears during the frequency change process is manifested as transient leakage. The larger the amplitude of the transient leakage waveform, the more drastic the frequency change during the frequency hopping process, which may cause more serious adjacent frequency interference. When at least one of the frequency leakage intensity or transient leakage waveform amplitude of the first sequence point reaches a predetermined reference threshold, it indicates that the leakage effect of this frequency hopping point is large, which may interfere with adjacent frequency signals or cause performance degradation. Therefore, it needs to be marked as an interference sequence point for parameter optimization or correction to avoid adverse effects on the normal operation of the filter. By setting reference thresholds to monitor and determine the frequency leakage intensity and transient leakage amplitude, the interference that may occur during the frequency hopping process can be effectively identified and processed to ensure that the filter always maintains optimal performance during high-speed frequency hopping.

[0023] In particular, as a feasible implementation, the first reference value is set to the mean of all frequency leakage intensity values ​​plus twice the standard deviation of the frequency leakage intensity values, and the second reference value is set to the mean of all transient leakage waveform amplitudes plus one times the standard deviation of the transient leakage waveform amplitude.

[0024] The reference value is set by adding the mean value plus the multiple of the standard deviation. The mean value reflects the average level of the leakage parameter within a period of time or in multiple frequency hopping points, and the standard deviation reflects the volatility or discreteness of the leakage parameter value. A larger standard deviation means that the parameter has a larger fluctuation range during the frequency hopping process, and there may be a larger jump amplitude or frequency leakage. By adding the multiple of the standard deviation, the system can set a wider tolerance range. This tolerance range not only takes into account common leakage parameters, but also covers extreme fluctuations or abnormal situations, thereby avoiding mislabeling caused by overly strict thresholds. Among them, the frequency leakage intensity value is set to the mean plus two times the standard deviation, which means that the system will more strictly identify those situations where the leakage intensity is much higher than the average level. The setting of 2 times the standard deviation helps to identify larger frequency leakage; the transient leakage waveform amplitude is set to the mean plus one times the standard deviation, which means that the volatility of transient leakage is usually large, so 1 times the standard deviation is adopted to ensure that more significant transient leakage is effectively detected, but not over-labeled. By using the mean and standard deviation to set the reference value, the scheme can dynamically adjust the interference identification standard according to the distribution of actual data, avoiding the inadaptability problem caused by the use of fixed thresholds.

[0025] Further, as a feasible implementation method, the frequency leakage intensity value is calculated and obtained by calculating the power spectrum density difference between the target frequency band and the adjacent frequency band; the transient leakage waveform amplitude is calculated and obtained by calculating the maximum overshoot amplitude value after frequency switching and the transition response of the target filter; let the maximum overshoot amplitude value be expressed as δ, let the transition response of the target filter be expressed as H(t), and let the output value of the target filter in the steady state be expressed as H final , then the maximum overshoot amplitude value calculation formula is expressed as: .

[0026] The frequency leakage intensity reflects the power difference between the target frequency band and its adjacent frequency band, indicating the impact of the signal leakage of the target frequency band on the adjacent frequency band; the greater the difference in power spectrum density, the higher the degree of signal leakage to the adjacent frequency band, which may lead to stronger adjacent frequency interference. This method can dynamically reflect the actual impact of frequency leakage, especially in high-frequency hopping or frequency selective transmission, and can effectively identify the degree of signal leakage to the adjacent frequency band. The maximum overshoot amplitude value represents the instantaneous maximum amplitude deviation of the filter after frequency switching, which is caused by the transient response during frequency switching. The overshoot amplitude refers to the maximum excessive deviation of the output signal compared to the steady-state value during the filter response process; overshoot usually occurs when the system switches from one frequency to another, especially when the frequency changes are large. The maximum overshoot amplitude value δ represents the maximum deviation during the transition process, that is, during the frequency switching process, the output of the filter may exceed the steady-state value and produce an overshoot, and the maximum overshoot amplitude value δ quantifies the size of this overshoot. The maximum overshoot amplitude value reflects the degree of transient fluctuation of the filter during the frequency switching process, and helps to quantify the interference or instability that may be caused during the frequency switching process. The transition response refers to the transient output response of the filter during the frequency switching process. The output of the filter will transition from the initial state to the steady-state value, and overshoot, oscillation and other phenomena may occur during the transition process. The maximum overshoot amplitude reflects the maximum amplitude deviation in this transition process and is an important indicator for measuring the leakage effect generated in the transient response. The max|H(t)| represents the maximum amplitude value in the transition response of the target filter, that is, the maximum deviation of the filter output signal during the entire transition process; usually when the frequency is switched, the filter will have a transient overshoot, that is, the output signal exceeds the steady-state value, which is the overshoot phenomenon. By obtaining the maximum amplitude value, the strongest transient effect in the filter response, that is, the maximum overshoot amplitude of the system, can be captured. The H final It represents the output value of the target filter in steady state, that is, the output value that is finally stabilized after the filter undergoes transient response after the frequency switching is completed.

[0027] Furthermore, as a feasible implementation method, the content of the exponential gradual transition method includes: The target transition interval is set with the modulation sequence point and the adjacent first sequence point as endpoints on the time axis, and the frequency value of the frequency hopping of the target filter at the corresponding sequence point is marked in the corresponding time sequence at the endpoint of the target transition interval, and the frequency value of the frequency hopping is represented as the initial frequency value f0 and the frequency hopping frequency value f in sequence along the chronological position. t , where t represents a time point on the time axis; let the target frequency change corresponding to each target transition interval in the preset frequency hopping implementation strategy be expressed as Δf, let the transition time constant be expressed as τ, Then the frequency hopping frequency value f in the target transition interval is t It is expressed as: .

[0028] On the time axis, select the modulation sequence point and the adjacent first sequence point as endpoints to determine a target transition interval. At the endpoints of the target transition interval, mark the frequency hopping frequency of the target filter at the corresponding sequence point. The f(t) represents the frequency at the current time t, and gradually transitions from the initial frequency value f0 to the target frequency value over time. The e -t / τ The meaning of is expressed as an exponential decay term, which is used to control the rate of frequency change and indicate the smoothness of the transition process. (1-e -t / τ ) means the smooth transition process from the initial frequency value f0 to the target frequency (f0+Δf). When time t=0, e -t / τ =1, so 1-e -t / τ =0, which means that the frequency at the initial moment f(t) = f0, that is, the filter remains at the initial frequency at the beginning. As time increases, e -t / τ Gradually decrease, (1-e -t / τ ) increases, the frequency f(t) will gradually increase until it reaches the target frequency (f0+Δf). When time approaches infinity, e -t / τ →0, then 1-e -t / τ →1, the frequency f(t) finally reaches the target frequency f0+Δf.

[0029] As a specific application, the frequency hopping range of the target filter is decomposed into a number of working frequency bands, and a piecewise exponential gradient transition function is used to perform a smooth gradient transition on the multi-working frequency hopping transformation between the modulation sequence point and the adjacent first sequence point.

[0030] The entire frequency hopping range of the target filter is divided into several frequency bands. Each working frequency band represents a relatively small frequency range, and the filter performs frequency hopping within these small ranges. This segmentation can control the frequency hopping process more finely and reduce transient leakage and interference generated when the frequency is switched. The segmented exponential gradient transition function means that within each working frequency band, the frequency change is no longer linear, but a segmented exponential gradient transition function is used for smooth transition. For each working frequency band, an exponential attenuation function is used to smoothly transition to the next frequency band to avoid too fast frequency jumps and reduce the impact and interference on the system. Multi-working frequency bands can more accurately control the frequency changes within each frequency band by decomposing the frequency hopping range into multiple frequency bands, avoiding instability caused by excessive or too fast frequency changes.

[0031] Further, as a feasible implementation method, a PID control method is used to dynamically adjust the transition time constant according to the difference between the target frequency and the current frequency, which includes: marking the actual frequency change of each target transition interval before correction, and calculating the frequency difference between the target frequency change and the actual frequency change; setting the error accumulation value of the target filter from running to the current moment and the error change rate value of the target filter frequency at the current moment, and using the gain coefficient of the PID control method as the weight value to perform weighted summation on the frequency difference, error accumulation value and error change rate value, and setting the summation result as the transition time constant; Where, the actual frequency change is expressed as Δf p , let the frequency difference between the target frequency change and the actual frequency change be expressed as E, and the gain coefficient corresponding to the frequency difference is the proportional gain coefficient, which is used to control the influence of the frequency difference on the time constant, wherein the calculation form of the frequency difference E is expressed as: E(t)=|Δf-Δf p |; The error accumulation value is expressed as , and the gain coefficient corresponding to the error accumulation value is the integral gain coefficient, which is used to control the influence of error accumulation on the time constant; the error change rate value is expressed as , and the gain coefficient corresponding to the error change rate value is a differential gain coefficient, which is used to control the influence of the error change rate on the time constant.

[0032] The PID control method is used to adjust the transition time constant using the difference (i.e., error) between the target frequency and the current frequency, the accumulated value of the error, and the rate of change of the error, so as to achieve a more accurate frequency transition. The target frequency change represents the expected change in the target filter frequency within the target transition interval, usually the change in the set frequency range. The actual frequency change represents the actual frequency change of the target filter, which may be affected by system characteristics, interference or other factors, and is usually different from the target frequency change. The error accumulation value reflects the accumulation of frequency errors from the starting moment to the current moment; the error change rate value represents the rate at which the error changes over time, i.e., the derivative of the error with respect to time; the proportional gain coefficient is used to control the effect of the frequency difference on the transition time constant. The larger the frequency difference, the greater the difference between the target frequency and the actual frequency, and the transition time constant should be adjusted accordingly to correct this difference. The PID control method directly adjusts the transition time constant through the frequency difference in proportional control to ensure that the system can make corrections in time when the frequency error is large; in integral control, the long-term errors in the system are compensated by controlling the accumulated error value to ensure that the persistent errors in the frequency hopping process are corrected; in differential control, the hysteresis of the system response is reduced by monitoring the rate of change of the frequency error. By introducing the PID control method to dynamically adjust the transition time constant, precise control of the target filter frequency hopping process is achieved. The PID control method combines proportional, integral and differential control, and can dynamically adjust the transition time constant according to the current frequency error, error accumulation and error change rate, thereby optimizing the smoothness, response speed and anti-interference ability in the frequency hopping process.

[0033] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A frequency hopping parameter tuning optimization method for a frequency hopping filter, characterized in that: The method includes: Step S1: the target filter performs frequency hopping according to a preset frequency hopping implementation strategy and keeps monitoring, and the frequency hopping records and leakage parameter values ​​of all frequency leakages obtained by monitoring are recorded as the first sequence point and the second sequence point on the time axis respectively; Step S2: Record the leakage parameter value of the frequency leakage and set a reference threshold, screen out the second sequence point whose leakage parameter value reaches the reference threshold and mark it as an interference sequence point, and mark the first sequence point closest to the interference sequence point as a modulation sequence point; Step S3: recording the frequency hopping filter parameters of the target filter corresponding to the occurrence of all first sequence points, and using an exponential gradual transition method to perform a gradual transition correction on the frequency hopping transformation between each modulation sequence point and its adjacent first sequence point; Step S4: re-label all the corrected modulation sequence points as first sequence points, and correct the frequency hopping filter parameters of the target filter at the corresponding first sequence points according to the frequency values ​​of the corrected first sequence points, and update the time positions of the corrected first sequence points and the corresponding frequency hopping filter parameters to the frequency hopping implementation strategy.

2. The method for tuning and optimizing frequency hopping parameters of a frequency hopping filter according to claim 1, characterized in that: The leakage parameter value includes a frequency leakage intensity value and a transient leakage waveform amplitude; the setting content of the reference threshold is that the frequency leakage intensity value and the transient leakage waveform amplitude correspond to a first reference value and a second reference value respectively; when at least one leakage parameter value among the frequency leakage intensity value and the transient leakage waveform amplitude recorded at the first sequence point reaches the corresponding reference threshold, the first sequence point is marked as an interference sequence point.

3. The method for tuning and optimizing frequency hopping parameters of a frequency hopping filter according to claim 1, characterized in that: The contents of the exponential gradient transition method include: The target transition interval is set with the modulation sequence point and the adjacent first sequence point as endpoints on the time axis, and the frequency value of the frequency hopping of the target filter at the corresponding sequence point is marked in the corresponding time sequence at the endpoint of the target transition interval, and the frequency value of the frequency hopping is represented as the initial frequency value f0 and the frequency hopping frequency value f in sequence along the chronological position. t , where t represents a time point on the time axis; let the target frequency change corresponding to each target transition interval in the preset frequency hopping implementation strategy be expressed as Δf, let the transition time constant be expressed as τ, Then the frequency hopping frequency value f in the target transition interval is t It is expressed as: .

4. The method for tuning and optimizing frequency hopping parameters of a frequency hopping filter according to claim 3, characterized in that: The frequency hopping range of the target filter is decomposed into a number of working frequency bands, and a piecewise exponential gradual transition function is used to perform a smooth gradual transition on the multi-working frequency hopping transformation between a modulation sequence point and an adjacent first sequence point.

5. The method for tuning and optimizing frequency hopping parameters of a frequency hopping filter according to claim 4, characterized in that: The PID control method is used to dynamically adjust the transition time constant according to the difference between the target frequency and the current frequency, which includes: marking the actual frequency change of each target transition interval before correction, and calculating the frequency difference between the target frequency change and the actual frequency change; setting the error accumulation value of the target filter from running to the current moment and the error change rate value of the target filter frequency at the current moment, and using the gain coefficient of the PID control method as the weight value to perform weighted summation on the frequency difference, error accumulation value and error change rate value, and setting the summation result as the transition time constant; Assume that the actual frequency change is expressed as Δf p , let the frequency difference between the target frequency change and the actual frequency change be expressed as E, and the gain coefficient corresponding to the frequency difference is the proportional gain coefficient, which is used to control the influence of the frequency difference on the time constant, wherein the calculation form of the frequency difference E is expressed as: E(t)=|Δf-Δf p |.

6. A method for tuning and optimizing frequency hopping parameters of a frequency hopping filter according to claim 5, characterized in that: The error accumulation value is expressed as , and the gain coefficient corresponding to the error accumulation value is an integral gain coefficient, which is used to control the influence of error accumulation on the time constant.

7. The method for tuning and optimizing frequency hopping parameters of a frequency hopping filter according to claim 5, characterized in that: The error change rate value is expressed as , and the gain coefficient corresponding to the error change rate value is a differential gain coefficient, which is used to control the influence of the error change rate on the time constant.

8. The method for tuning and optimizing frequency hopping parameters of a frequency hopping filter according to claim 2, characterized in that: The first reference value is set to the mean of all frequency leakage intensity values ​​plus twice the standard deviation of the frequency leakage intensity values, and the second reference value is set to the mean of all transient leakage waveform amplitudes plus one times the standard deviation of the transient leakage waveform amplitude.

9. The method for tuning and optimizing frequency hopping parameters of a frequency hopping filter according to claim 2, characterized in that: The frequency leakage intensity value is obtained by calculating the difference in power spectrum density between the target frequency band and the adjacent frequency band; the transient leakage waveform amplitude is obtained by calculating the maximum overshoot amplitude value after frequency switching and the transition response of the target filter.

10. The method for tuning and optimizing frequency hopping parameters of a frequency hopping filter according to claim 9, characterized in that: Let the maximum overshoot amplitude be denoted as δ, let the transient response of the target filter be denoted as H(t), and let the output value of the target filter in the steady state be denoted as H final , then the maximum overshoot amplitude value calculation formula is expressed as: .

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