A method for optimizing the hopping parameter tuning of a frequency hopping filter

Abstract

The present invention discloses a hopping parameter tuning and optimization method for a frequency hopping filter, which relates to the technical field of filters. The method includes: Step S1: Denote all the frequency hops and frequency leakages of the frequency hopping implementation strategy as the first sequence points and the second sequence points respectively on the time axis; Step S2: Screen out the second sequence points whose leakage parameter values reach the reference threshold and label them as interference sequence points, and label the first sequence point closest to the interference sequence point as the modulation sequence point; Step S3: Use the exponential gradual transition method to perform gradual transition correction on the frequency hopping transformation between each modulation sequence point and its adjacent first sequence point; Step S4: Update the corrected first sequence points to the frequency hopping implementation strategy. By setting a reference threshold to screen out leakage points and dynamically correcting the modulation sequence points and frequency hopping parameters, the present invention has the beneficial effect of significantly improving the frequency hopping working stability and low interference performance of the frequency hopping filter.

Description

Technical Field

[0001] The present invention relates to the technical field of filters, and particularly relates to a method for tuning and optimizing hopping parameters 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 communication, military, Bluetooth, satellite communication and other fields, and has the advantages of anti-interference, strong confidentiality, and improved spectrum utilization. The main function of a frequency hopping filter is to isolate the frequency band occupied by a signal from other interfering signals in adjacent frequency bands. Since the frequency of a frequency hopping signal changes rapidly and irregularly, the filter needs to have strong frequency selectivity to effectively filter out unwanted frequency components and ensure that the signal in the target frequency band can be transmitted clearly.

[0003] In the existing frequency hopping communication process, adjacent frequency interference often occurs due to transient leakage. Adjacent frequency interference refers to the failure of the filter to completely isolate unwanted signals, resulting in the leakage of the frequency components of the signal into adjacent frequency bands, thereby affecting the signals in other frequency bands. If the frequency hopping rate is too fast and the transition between frequency switches is not smooth, the frequency hopping signal may generate strong transient leakage at the moment of frequency switching, and 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 hopping is too fast, the non-smooth transition generated by the frequency hopping signal during the frequency switching process will still cause transient leakage; the intensity of transient leakage is directly related to the severity of the switching frequency. When the frequency hopping rate is too high, the process of frequency switching may be too hasty to avoid strong transient fluctuations. At present, the accuracy of correcting adjacent frequency interference for frequency hopping filters in the existing technology is not good, mainly relying on debugging filter parameters based on a large number of correction samples, making the work cost of correcting adjacent frequency interference parameters high and the accuracy low. Summary of the Invention

[0004] The present invention provides a method for tuning and optimizing hopping parameters for a frequency hopping filter, which solves the problem of low accuracy in correcting adjacent frequency interference caused by transient leakage during high-speed frequency hopping of existing frequency hopping filters.

[0005] The present invention is achieved by the following technical solutions:

[0006] A method for tuning and optimizing hopping parameters for a frequency hopping filter, the method comprising:

[0007] Step S1: Operating the target filter according to a preset frequency hopping implementation strategy and keeping monitoring, and respectively recording all frequency leakage hopping records and leakage parameter values obtained by monitoring as a first sequence of points and a second sequence of points on the time axis;

[0008] Step S2: Record the leakage parameter values of frequency leakage and set a reference threshold. Screen out the second sequence points whose leakage parameter values reach the reference threshold and label them as interference sequence points, and label the first sequence point closest to the interference sequence point as a modulation sequence point;

[0009] Step S3: Record the frequency hopping filtering parameters of the target filter corresponding to all the first sequence points. Use the 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;

[0010] Step S4: Relabel all the corrected modulation sequence points as first sequence points, and correct the frequency hopping filtering parameters of the target filter at the corresponding first sequence points according to the frequency values of the corrected first sequence points. Update the time positions and corresponding frequency hopping filtering parameters of the corrected first sequence points to the frequency hopping implementation strategy.

[0011] Further, the leakage parameter values include a frequency leakage intensity value and an amplitude of a transient leakage waveform; the setting content of the reference threshold is that for the frequency leakage intensity value and the amplitude of the transient leakage waveform, they respectively correspond to a first reference value and a second reference value; when at least one of the leakage parameter values of the frequency leakage intensity value and the amplitude of the transient leakage waveform recorded by the first sequence point reaches the corresponding reference threshold, label the first sequence point as an interference sequence point.

[0012] Further, the content of the exponential gradual transition method includes:

[0013] Set a target transition interval on the time axis with the modulation sequence point and the adjacent first sequence point as endpoints. Mark the frequency values of the frequency hopping of the target filter at the corresponding sequence points in the order of corresponding time at the endpoints of the target transition interval, and sequentially represent the frequency values of the frequency hopping along the successive positions as an initial frequency value f0 and a frequency hopping frequency value f(t), where t represents a time point on the time axis; assume that the target frequency change amount set for each target transition interval in the preset frequency hopping implementation strategy is represented as Δf, and assume that the transition time constant is represented as τ,

[0014] Then the frequency hopping frequency value f(t) on the target transition interval is expressed as: .

[0015] Further, disassemble the frequency hopping range of the target filter into a number of working frequency bands, and use a piecewise exponential gradual transition function to perform a smooth gradual transition on the multi - working - band frequency hopping transformation between the modulation sequence point and the adjacent first sequence point.

[0016] Further, 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. The content includes: marking the actual frequency change amount before correction in each target transition interval, and calculating the frequency difference between the target frequency change amount and the actual frequency change amount; setting the error accumulation value of the target filter from the start of operation to the current moment and the error change rate value of the target filter at the current moment frequency, 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;

[0017] Let the actual frequency change amount be denoted as Δf p , let the frequency difference between the target frequency change amount and the actual frequency change amount be denoted as E(t), 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. Then the calculation form of the frequency difference E(t) is expressed as: E(t) = |Δf - Δf p |.

[0018] Further, the error accumulation value is denoted 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.

[0019] Further, the error change rate value is denoted as , and the gain coefficient corresponding to the error change rate value is the differential gain coefficient, which is used to control the influence of the error change rate on the time constant.

[0020] Further, the first reference value is set as the mean value of all frequency leakage intensity values plus twice the standard deviation of the frequency leakage intensity values, and the second reference value is set as the mean value of all transient leakage waveform amplitudes plus once the standard deviation of the transient leakage waveform amplitudes.

[0021] Further, the frequency leakage intensity value is calculated and obtained through the power spectral density difference degree 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.

[0022] Further, let the maximum overshoot amplitude value be denoted as δ, let the transition 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 calculation formula of the maximum overshoot amplitude value is expressed as: .

[0023] Compared with the prior art, the present invention screens leakage points by setting a reference threshold, uses an exponential gradient transition method to correct the change between frequency hopping points, avoids too fast or sudden frequency hopping, and can dynamically correct the 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, and having 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

[0024] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, form a part of this application, and do not limit the embodiments of the present invention. In the drawings:

[0025] Figure 1 It is a flowchart of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0026] To make the objectives, technical solutions, and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below in conjunction with the embodiments and the drawings. The illustrative embodiments and descriptions of the present invention are only used to explain the present invention and do not limit the present invention. Embodiment

[0027] As Figure 1 shown, this embodiment is a frequency hopping parameter tuning and optimization method for a frequency hopping filter, and the method includes:

[0028] Step S1: Make the target filter perform frequency hopping work according to a preset frequency hopping implementation strategy and keep monitoring, and record all frequency leakage frequency hopping records and leakage parameter values obtained from the monitoring as the first sequence points and the second sequence points on the time axis respectively;

[0029] Step S2: Record the leakage parameter values of the frequency leakage and set a reference threshold, screen out the second sequence points whose leakage parameter values reach the reference threshold and label them as interference sequence points, and label the first sequence point closest to the interference sequence point as the modulation sequence point;

[0030] Step S3: Record the frequency hopping filtering parameters of the target filter corresponding to all the first sequence points, and use the exponential gradient transition method to perform gradient transition correction on the frequency hopping transformation between each modulation sequence point and its adjacent first sequence point;

[0031] Step S4: Relabel all the corrected modulation sequence points as the first sequence points, correct the frequency hopping filtering 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 moment positions and the corresponding frequency hopping filtering parameters of the corrected first sequence points to the frequency hopping implementation strategy.

[0032] The design of a frequency-hopping filter usually requires rapid switching between different frequencies. However, during this hopping process, due to physical system limitations such as bandwidth limitations and response speed, transient effects will occur when the filter hops, resulting in signal energy leakage into other frequency regions, which is the so-called "frequency leakage". Frequency leakage is mainly caused by the transient response of the filter or the signal during the frequency-hopping process, and it is manifested as the unintentional propagation of signal energy into the frequency band that should have been 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, indicating the behavior of controlling the filter during the frequency-hopping process; the frequency-hopping implementation strategy covers multiple aspects such as frequency selection, timing of frequency switching, hopping amplitude, and frequency-hopping rate during the frequency-hopping process of the filter. The so-called frequency leakage refers to the expansion or overflow of the signal frequency into the adjacent frequency range during the frequency-hopping process of the filter, causing unnecessary interference. The leakage parameter value can be a numerical index describing the leakage intensity, frequency range, or leakage rate. For example, in some implementation processes, it can be statistically the amplitude of the leakage signal, frequency offset, time characteristics of the leakage frequency, etc. The frequency-hopping record refers to the frequency value, time, and its corresponding filter state of each hop during the high-speed frequency-hopping process of the target filter. The first sequence of points refers to marking all frequency-hopping events (i.e., the time and frequency value of the filter frequency hop) on the time axis. The time and hopping frequency of each frequency hop form a "time-frequency" pair, and these points form the first sequence on the time axis. The second sequence of points refers to marking the time of all frequency leakage occurrences 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.

[0033] Furthermore, in order to effectively screen out the leakage points that cause significant interference to the system, a reference threshold needs to be set. The reference threshold represents the maximum tolerance range of the intensity or frequency offset of the leakage signal and belongs to a preset standard. When the degree of frequency leakage reaches the reference threshold standard, it is considered that the frequency leakage has an impact on the system and intervention and correction must be carried out. At this time, the corresponding time point is determined as 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 in adjacent frequency bands. The reference threshold can be set based on historical experience or the mean value of historical data, or can be set through experimental simulation. After the interference sequence points are determined, the frequency hopping sequence points adjacent to the interference points are found, that is, the first sequence points that are about to perform frequency hopping or have just completed frequency hopping. These points are the frequency hopping signal points closest to the interference points and belong to the "modulation sequence points" that most need to be adjusted. 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 filtering 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 to ensure that the filter can work stably and effectively during the conversion between different frequencies. In the specific implementation process, the frequency hopping filtering parameters of the target filter may include relevant parameters such as the center frequency, bandwidth gain, filter order, and harmonic phase response. The exponential gradual transition method is a mathematical method commonly used to smooth the transition in a changing process to correct mutations or drastic changes. If the frequency needs to change from one value to another, a direct jump may cause signal instability or interference. Through the exponential gradual transition, the frequency change can be gradually slowed down within a certain time, thereby reducing the adverse effects brought by mutations. In a frequency hopping filter, when the frequency hopping parameters change, the exponential gradual transition will make the frequency change relatively quickly at the beginning and then gradually slow down over time, finally achieving a smooth transition, avoiding drastic jumps in the frequency during the change process, thereby reducing the transient effects and frequency leakage during the frequency hopping process, and further reducing interference and errors. According to the corrected frequency value of the first sequence point, the parameters of the filter are readjusted to make it adapt to the corrected frequency state, that is, the working frequency, gain, bandwidth and other parameters of the filter 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 operations according to the optimized parameters during actual operation.

[0034] Further, as a feasible implementation, 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 respectively correspond to a first reference value and a second reference value; when at least one of the leakage parameter values of the frequency leakage intensity value and the transient leakage waveform amplitude recorded by the first sequence of points reaches the corresponding reference threshold, the first sequence of points is marked as an interference sequence point.

[0035] The frequency leakage intensity value refers to the magnitude or energy of such a leakage signal. The larger the frequency leakage intensity value, the stronger the energy leaked into 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. Usually, the magnitude of the frequency leakage signal or the energy of the leakage signal is expressed in decibels (dB). The transient leakage waveform amplitude refers to the amplitude of the instantaneous signal leakage caused by the frequency or signal transient change during signal processing or frequency hopping. In a frequency hopping system, the frequency change is usually gradual, but if the frequency change is too fast or not smooth, it may cause discontinuous waveforms or short-term drastic changes in the spectrum, and this drastic change is called a transient effect; the instantaneous peak (i.e., the highest amplitude point) during the frequency change process is manifested as transient leakage. The larger the transient leakage waveform amplitude, 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 the transient leakage waveform amplitude of the first sequence of points reaches a predetermined reference threshold, it indicates that the leakage effect of this frequency hopping point is relatively large, which may interfere with the adjacent frequency signal 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 the reference threshold to monitor and determine the frequency leakage intensity and the transient leakage amplitude, it is possible to effectively identify and handle the interference that may occur during the frequency hopping process, and ensure that the filter always maintains the best performance during high-speed frequency hopping.

[0036] Particularly, 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 once the standard deviation of the transient leakage waveform amplitudes.

[0037] The reference value is set by the method of adding a multiple of the standard deviation to the mean. The mean reflects the average level of the leakage parameter over a period of time or among multiple hopping frequencies. The standard deviation reflects the volatility or dispersion degree of the leakage parameter values. 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 a multiple of the standard deviation, the system can set a wider tolerance range. This tolerance range not only considers common leakage parameters but also covers extreme fluctuations or abnormal situations, thus avoiding mislabeling caused by overly strict thresholds. Among them, the frequency leakage intensity value is set to the mean plus twice the standard deviation, indicating that the system will relatively strictly identify those situations where the leakage intensity is much higher than the average level. The setting of twice the standard deviation helps to identify larger frequency leakages; the transient leakage waveform amplitude is set to the mean plus one standard deviation, indicating that the volatility of transient leakage is usually large. Therefore, one standard deviation is adopted to ensure the effective detection of relatively significant transient leakages without over-labeling. By using the mean and standard deviation to set the reference value, the scheme can dynamically adjust the interference recognition standard according to the distribution of actual data, avoiding the inadaptability problem caused by using a fixed threshold.

[0038] Further, as a feasible implementation manner, the frequency leakage intensity value is calculated and obtained through the power spectral density difference degree 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 represented as δ, let the transition response of the target filter be represented as H(t), and let the output value of the target filter under steady state be represented as H final , then the calculation formula for the maximum overshoot amplitude value is expressed as: .

[0039] The frequency leakage intensity reflects the power difference between the target frequency band and its adjacent frequency bands, indicating the impact of signal leakage in the target frequency band on adjacent frequency bands; the greater the power spectral density difference, the higher the degree of signal leakage into adjacent frequency bands, which may lead to stronger adjacent channel interference. This method can dynamically reflect the actual impact of frequency leakage, especially in the case of high-frequency hopping or frequency-selective transmission, and can effectively identify the degree of signal leakage into adjacent frequency bands. 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 especially when the frequency changes significantly when the system switches from one frequency to another. The maximum overshoot amplitude value δ represents the maximum deviation during the transient process, that is, during the frequency switching process, the output of the filter may exceed the steady-state value, generating 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 frequency switching, helping to quantify the interference or instability phenomena that may be caused during frequency switching. The transient response refers to the transient output response of the filter during frequency switching. The output of the filter will transition from the initial state to the steady-state value, and phenomena such as overshoot and oscillation may occur during the transition process. The maximum overshoot amplitude reflects the maximum amplitude deviation during 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 during the transient response process of the target filter, that is, it represents the maximum deviation degree of the output signal of the filter during the entire transient process; usually during frequency switching, the filter will have an instantaneous 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 can be captured, that is, the maximum overshoot amplitude of the system. The H final represents the output value of the target filter in the steady state, that is, after the frequency switching is completed, after the filter undergoes the transient response, the finally stabilized output value.

[0040] Further, as a feasible implementation manner, the content of the exponential gradient transition method includes:

[0041] Set a target transition interval with the modulation sequence point and the adjacent first sequence point as endpoints on the time axis, mark the frequency values of the frequency hopping of the target filter at the corresponding sequence points in the order of corresponding time at the endpoints of the target transition interval, and sequentially represent the frequency values of the frequency hopping as the initial frequency value f0 and the frequency hopping frequency value f(t) along the sequence of positions, where t represents the time point on the time axis; assume that the target frequency change amount set for each target transition interval in the preset frequency hopping implementation strategy is represented by Δf, and assume that the transition time constant is represented by τ,

[0042] The hopping frequency value f(t) in the target transition interval is expressed as: .

[0043] 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 hopping frequencies of the target filter at the corresponding sequence points respectively. The f(t) represents the frequency at the current moment t and gradually transitions from the initial frequency value f0 to the target frequency value over time. The e -t / τ is defined as an exponential decay term, which is used to control the rate of frequency change and represents the smoothness of the transition process. The meaning of (1 - e -t / τ ) represents the smooth transition process of the frequency from the initial frequency value f0 to the target frequency (f0 + Δf). When 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 decreases, (1 - e -t / τ ) increases, and the frequency f(t) will gradually increase until it reaches the target frequency (f0 + Δf). When time approaches infinity, e -t / τ →0, at this time 1 - e -t / τ →1, and the frequency f(t) finally reaches the target frequency f0 + Δf.

[0044] As a specific application, the 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 - band hopping transformation between the modulation sequence point and the adjacent first sequence point.

[0045] The entire 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 hops within these small ranges. This segmentation can more finely control the hopping process and reduce the transient leakage and interference generated during frequency switching. The piecewise exponential gradual transition function means that within each working frequency band, the change of frequency is no longer linear, but a piecewise exponential gradual transition function is used for smooth transition. For each working frequency band, an exponential decay function is used to smoothly transition to the next frequency band, avoiding too fast frequency jumps and reducing the impact and interference on the system. Multiple working frequency bands can more precisely control the frequency change within each frequency band by decomposing the hopping range into multiple frequency bands, avoiding the instability caused by too large or too fast frequency changes.

[0046] Further, as a feasible implementation, 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. The content includes: marking the actual frequency change amount before correction in each target transition interval, and calculating the frequency difference between the target frequency change amount and the actual frequency change amount; setting the error accumulation value of the target filter from the start of operation to the current moment and the error change rate value of the target filter at the current moment frequency, 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;

[0047] Among them, let the actual frequency change amount be expressed as Δf p , let the frequency difference between the target frequency change amount and the actual frequency change amount be expressed as E(t), 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. Then the calculation form of the frequency difference E(t) 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 the differential gain coefficient, which is used to control the influence of the error change rate on the time constant.

[0048] The PID control method is used to adjust the transition time constant by using the difference (i.e., error) between the target frequency and the current frequency, the cumulative 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 amount represents the expected change amount of the target filter frequency within the target transition interval, usually the change amount of the set frequency range. The actual frequency change amount represents the frequency change amount actually completed by the target filter, which may be affected by system characteristics, interference or other factors, and is usually different from the target frequency change amount. The error cumulative value reflects the accumulation of frequency errors from the starting moment to the current moment; the error rate of change value represents the rate of change of the error with time, that is, the derivative of the error with respect to time; the proportional gain coefficient is used to control the influence 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 makes corrections in a timely manner when the frequency error is large; in integral control, it compensates for the long-term existing errors in the system by controlling the error cumulative value to ensure that the continuous errors in the frequency hopping process are corrected; in derivative control, it reduces the hysteresis of the system response 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 during the frequency jump of the target filter frequency is achieved. The PID control method combines proportional, integral, and derivative controls, and can dynamically adjust the transition time constant according to the current frequency error, error accumulation, and error rate of change, thereby optimizing the smoothness, response speed, and anti-interference ability during frequency hopping.

[0049] The specific implementation manners described above further elaborate on the purpose, technical solutions, and beneficial effects of the present invention. It should be understood that the above description is only the specific implementation manners of the present invention and is not used to limit the protection scope of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A hopping parameter tuning and optimization method for a frequency hopping filter, characterized in that The method includes: Step S1: The target filter performs frequency hopping work according to a preset frequency hopping implementation strategy and keeps monitoring. All the frequency leakage frequency hopping records and leakage parameter values obtained from the monitoring are respectively recorded as the first sequence points and the second sequence points on the time axis. Step S2: Record the leakage parameter values of the frequency leakage and set a reference threshold. Screen out the second sequence points whose leakage parameter values reach the reference threshold and label them as interference sequence points, and label the first sequence point closest to the interference sequence point as the modulation sequence point. Step S3: Record the frequency hopping filtering parameters of the target filter corresponding to all the first sequence points, and use the exponential gradual transition method to perform gradual transition correction on the frequency hopping transformation between each modulation sequence point and its adjacent first sequence point. Step S4: Relabel all the corrected modulation sequence points as the first sequence points, correct the frequency hopping filtering 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 moment positions and corresponding frequency hopping filtering parameters of the corrected first sequence points to the frequency hopping implementation strategy. The leakage parameter values include the frequency leakage intensity value and the transient leakage waveform amplitude. The setting content of the reference threshold is that for the frequency leakage intensity value and the transient leakage waveform amplitude, they respectively correspond to a first reference value and a second reference value. When at least one of the leakage parameter values, namely 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 labeled as an interference sequence point. The content of the exponential gradual transition method includes: On the time axis, set a target transition interval with the modulation sequence point and the adjacent first sequence point as endpoints. Mark the frequency values of the frequency hopping of the target filter at the corresponding sequence points in the order of corresponding time at the endpoints of the target transition interval, and successively represent the frequency values of the frequency hopping as the initial frequency value f0 and the frequency hopping frequency value f(t) along the successive positions, where t represents the moment point on the time axis. Assume that the target frequency change amount corresponding to each target transition interval set in the preset frequency hopping implementation strategy is represented as Δf, and assume that the transition time constant is represented as τ. Then the hopping frequency value f(t) in the target transition interval is expressed as: .

2. A hopping parameter tuning and optimization method for a frequency hopping filter according to claim 1, characterized in that Decompose the frequency hopping range of the target filter into a number of working frequency bands, and use a piecewise exponential gradual transition function to perform smooth gradual transition on the multi - working - band frequency hopping transformation between the modulation sequence point and the adjacent first sequence point.

3. A hopping parameter tuning and optimization method for a frequency hopping filter according to claim 2, characterized in that, Use the PID control method to dynamically adjust the transition time constant according to the difference between the target frequency and the current frequency. The content includes: Mark the actual frequency change amount before correction for each target transition interval, and calculate the frequency difference between the target frequency change amount and the actual frequency change amount. Set the error accumulation value of the target filter from operation to the current moment and the error change rate value of the frequency of the target filter at the current moment, and use 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 set the summation result as the transition time constant. Let the actual frequency change be denoted as Δf p , let the frequency difference between the target frequency change and the actual frequency change be denoted as E(t), 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. Then the calculation form of the frequency difference E(t) is expressed as: E(t) = |Δf - Δf p |.

4. A hopping parameter tuning and optimization method for a frequency hopping filter according to claim 3, characterized in that, 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.

5. A hopping parameter tuning and optimization method for a frequency hopping filter according to claim 3, characterized in that The error change rate value is expressed as , and the gain coefficient corresponding to the error change rate value is the differential gain coefficient, which is used to control the influence of the error change rate on the time constant.

6. A hopping parameter tuning and optimization method for a frequency hopping filter according to claim 1, characterized in that, Set the first reference value as the mean value of all frequency leakage intensity values plus twice the standard deviation of the frequency leakage intensity values, and set the second reference value as the mean value of all transient leakage waveform amplitudes plus the standard deviation of the transient leakage waveform amplitudes.

7. A hopping parameter tuning and optimization method for a frequency hopping filter according to claim 1, characterized in that, The frequency leakage intensity value is calculated and obtained through the power spectral density difference between the target frequency band and the adjacent frequency bands; 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.

8. A hopping parameter tuning and optimization method for a frequency hopping filter according to claim 7, characterized in that Let the maximum overshoot amplitude value 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 calculation formula for the maximum overshoot amplitude value is expressed as: .

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