Method, system, receiver and medium for interference monitoring and mitigation of gnss signals

Abstract

The application provides a GNSS signal interference monitoring and suppression method, system, receiver and medium, and particularly relates to the technical field of satellite navigation communication, and the scheme comprises the following steps: obtaining an intermediate frequency signal based on a received GNSS signal; performing interference detection on the intermediate frequency signal based on the differential cumulative power spectrum of the intermediate frequency signal, identifying the type of the interference signal according to the characteristic parameters of the interference signal, setting a notch frequency, performing filter processing on the intermediate frequency signal, and obtaining a target signal and a filtered signal; evaluating the filtered signal according to the energy of the signal, and when the evaluation of the filtered signal is invalid, re-identifying the characteristic parameters of the interference signal, adjusting the notch frequency for filter processing, and continuing until the evaluation is valid. The scheme can dynamically detect, identify and adjust the notch frequency of the interference signal in the environment, so that the interference signal can be effectively detected and adaptively suppressed, thereby improving the anti-interference performance of a single-antenna GNSS receiver in various interference environments.

Description

Technical Field

[0001] This invention relates to the field of satellite navigation and communication technology, and in particular to a method, system, receiver, and medium for monitoring and suppressing interference with GNSS signals. Background Technology

[0002] Position, navigation, and time (PNT) technology is widely used in various fields such as civilian navigation, finance and trade, the Internet of Things, autonomous driving, and smart cities. Currently, the Global Navigation Satellite System (GNSS) is one of the important sources of PNT information. However, the inherent vulnerability of GNSS signals makes them easily susceptible to interference from various radio frequency signals, such as radio signals broadcast by VHF / UHF television antennas, high-power continuous wave interference emitted by portable jammers, frequency sweep interference, and multiple continuous wave interference. These high-power electromagnetic signals can seriously affect the use of GNSS and may even threaten the safety of society, users' property, and lives.

[0003] Since GNSS receivers themselves lack the ability to suppress interference, improving their anti-interference capability is a pressing issue. Existing technologies primarily employ two methods for GNSS receiver anti-interference: multi-antenna technology and single-antenna technology. Multi-antenna technology uses beamforming to reduce signals from the direction of interference while amplifying useful signals from other directions, thus suppressing GNSS interference. However, it suffers from high hardware costs, high computational complexity, and a large computational load. Single-antenna technology, widely used in civilian applications such as mobile phones, smart wearables, and navigation devices, offers advantages such as small size, low hardware costs, low computational complexity, and a small computational load. Currently, research on anti-interference techniques for single-antenna receivers mainly focuses on environments with specific types of interference. However, in real-world environments, the type of interference signal is often unknown and randomly changing, resulting in poor anti-interference capabilities for single-antenna GNSS receivers suitable for specific interference types. Summary of the Invention

[0004] In view of the shortcomings of the prior art, the purpose of this invention is to provide a method, system, receiver and medium for GNSS signal interference monitoring and suppression, aiming to solve the problem of poor anti-interference capability of single-antenna GNSS receivers in the prior art.

[0005] To achieve the above objectives, the first aspect of the present invention provides a method for monitoring and suppressing interference with GNSS signals, comprising the following steps:

[0006] Based on the received GNSS signal, the intermediate frequency signal is obtained;

[0007] The intermediate frequency signal is subjected to spectral estimation to obtain the differential cumulative power spectrum of the intermediate frequency signal;

[0008] If the differential cumulative power spectrum of the intermediate frequency signal exceeds a preset differential cumulative power spectrum threshold, an interference warning signal is issued, and the characteristic parameters of the interference signal are obtained using the differential cumulative power spectrum.

[0009] The notch frequency is set according to the characteristic parameters of the interference signal, and the intermediate frequency signal is filtered based on the notch frequency to obtain the target signal and the filtered signal.

[0010] The filtered signal is evaluated based on the energy of the signal. If the filtered signal is deemed invalid, the characteristic parameters of the interference signal are re-evaluated, the notch frequency is adjusted, and the intermediate frequency signal is re-filtered until the evaluated filtered signal is valid. If the filtered signal is deemed valid, the target signal is output.

[0011] Optionally, the step of performing spectral estimation on the intermediate frequency signal to obtain the differential cumulative power spectrum of the intermediate frequency signal includes:

[0012] The power spectral density of the intermediate frequency signal is obtained, and the power spectral density is integrated and normalized to obtain the normalized cumulative spectral density.

[0013] Based on the normalized cumulative spectral density and the preset cumulative spectral density reference value, the differential cumulative power spectrum of the intermediate frequency signal is obtained.

[0014] Optionally, the step of determining the differential cumulative power spectrum threshold includes:

[0015] Historical data of GNSS signals are acquired, and based on the historical data of GNSS signals, the fluctuation range of the differential cumulative power spectrum of the intermediate frequency signal is obtained;

[0016] Based on the fluctuation range of the differential cumulative power spectrum of the intermediate frequency signal, the mean and variance of the differential cumulative power spectrum are obtained, and based on the mean and variance, the threshold value of the differential cumulative power spectrum is determined.

[0017] Optionally, obtaining the characteristic parameters of the interference signal using the differential cumulative power spectrum includes:

[0018] Parameters and types of several existing interference signals are collected in advance, and differential cumulative power spectrum models of existing interference signals are established based on the parameters and types of each existing interference signal to obtain a model database;

[0019] The characteristic parameters of the differential cumulative power spectrum are extracted, and the characteristic parameters of the interference signal are obtained by using the characteristic parameters of the differential cumulative power spectrum and the differential cumulative power spectrum model of each of the existing interference signals.

[0020] Optionally, if the pre-established differential cumulative power spectrum models of each of the existing interference signals do not match the type of the interference signal, then after obtaining the characteristic parameters of the interference signal, the method further includes:

[0021] Based on the characteristic parameters of the interference signal, the type of interference signal is determined;

[0022] Based on the characteristic parameters and type of the interference signal, a differential cumulative power spectrum model of the interference signal is constructed, and the model database is updated.

[0023] Optionally, the characteristic parameters of the interference signal include at least the interference signal frequency and the number of interference signals, and an adaptive notch filter is used to filter the intermediate frequency signal. The step of setting the notch frequency according to the characteristic parameters of the interference signal and filtering the intermediate frequency signal based on the notch frequency to obtain the target signal and the filtered signal includes:

[0024] The number of adaptive notch filters is set based on the number of interference signals.

[0025] Based on the frequency of the interference signal, adjust the initial notch frequency of the adaptive notch filter;

[0026] The intermediate frequency signal is filtered based on the initial notch frequency of each of the adaptive notch filters to obtain the target signal and the filtered signal.

[0027] Optionally, evaluating the effectiveness of the filtered signal includes:

[0028] If the difference between the energy of the filtered signal and the energy of the standard GNSS signal is less than or equal to a preset energy threshold, the filtered signal is determined to be invalid; otherwise, the filtered signal is determined to be valid.

[0029] A second aspect of the present invention provides a GNSS signal interference monitoring and suppression system, the system comprising:

[0030] The receiver front-end preprocessing unit is used to obtain the intermediate frequency signal based on the received GNSS signal;

[0031] The DCSP interference warning unit is used to perform spectrum estimation on the intermediate frequency signal to obtain the differential cumulative power spectrum of the intermediate frequency signal; if the differential cumulative power spectrum of the intermediate frequency signal exceeds a preset differential cumulative power spectrum threshold, an interference warning signal is issued.

[0032] The DCSP interference identification unit is used to obtain the characteristic parameters of the interference signal based on the warning information of the DCSP interference warning module and the differential cumulative power spectrum.

[0033] The parameter matching notch filter unit is used to set the notch frequency according to the characteristic parameters of the interference signal, and to filter the intermediate frequency signal based on the notch frequency to obtain the target signal and the filtered signal.

[0034] The filtering evaluation and optimization unit is used to evaluate the filtered signal based on the signal energy. When the evaluation of the filtered signal is invalid, the characteristic parameters of the interference signal are re-estimated, the notch frequency is adjusted, and the intermediate frequency signal is re-filtered until the evaluated filtered signal is valid. When the evaluation of the filtered signal is valid, the target signal is output.

[0035] A third aspect of the present invention provides a single-antenna anti-interference receiver, wherein the single-antenna anti-interference receiver stores a GNSS signal interference monitoring and suppression program, and when the GNSS signal interference monitoring and suppression program is executed by a processor, it implements any of the steps of the above-described GNSS signal interference monitoring and suppression method.

[0036] A fourth aspect of the present invention provides a computer-readable storage medium storing a GNSS signal interference monitoring and suppression program, wherein the GNSS signal interference monitoring and suppression program, when executed by a processor, implements the steps of any of the above-described GNSS signal interference monitoring and suppression methods.

[0037] Compared with existing technologies, the beneficial effects of this solution are as follows:

[0038] This invention obtains an intermediate frequency (IF) signal based on a received GNSS signal, and then obtains the differential cumulative power spectrum of the IF signal through spectral estimation. Based on the differential cumulative power spectrum of the IF signal, interference detection is performed on the IF signal, and the type of interference signal is identified according to the characteristic parameters of the interference signal. A notch filter frequency is then set to filter the IF signal to obtain the target signal and the filtered signal. The filtered signal is then evaluated based on the signal energy, and if the evaluation of the filtered signal is ineffective, the notch filter frequency is adjusted in time, and the filtering process is performed again to obtain the effectively filtered target signal.

[0039] As can be seen, this invention can not only issue a warning when interference signals are detected, but also automatically identify the type of interference. Furthermore, when the filtering effect is detected to be ineffective, it can determine the change in the type of interference signal and adjust the filtering frequency in a timely manner. This enables dynamic detection and identification of interference signals in the environment, as well as adjustment of the notch filter frequency, to ensure that interference signals are effectively detected and suppressed, thereby improving the anti-interference performance of a single-antenna GNSS receiver against various interference environments. Attached Figure Description

[0040] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0041] Figure 1 This is a schematic diagram of the GNSS signal interference monitoring and suppression system of the present invention;

[0042] Figure 2 This is a flowchart of the GNSS signal interference monitoring and suppression method of the present invention;

[0043] Figure 3 This is a schematic diagram of the differential power spectrum under different interference environments according to the present invention;

[0044] Figure 4 This is a schematic diagram illustrating the influence of the smoothing factor and forgetting factor of this invention on the continuous wave filtering effect. Detailed Implementation

[0045] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of the invention. However, those skilled in the art will understand that the invention can be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods are omitted so as not to obscure the description of the invention with unnecessary detail.

[0046] It should be understood that, when used in this specification and the appended claims, the term "comprising" indicates the presence of the described features, integrals, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0047] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0048] It should also be further understood that the term "and / or" as used in this specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0049] As used in this specification and the appended claims, the term "if" may be interpreted, depending on the context, as "when," "once," "in response to determination," or "in response to detection." Similarly, the phrases "if determined" or "if detected [the described condition or event]" may be interpreted, depending on the context, as meaning "once determined," "in response to determination," "once detected [the described condition or event]," or "in response to detection [the described condition or event]."

[0050] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0051] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0052] Currently, in the anti-interference aspect of single-antenna GNSS receivers, methods such as Robust Interference Mitigation (RIM), including time-domain complex signal processing, frequency-domain complex signal processing, and time-domain and frequency-domain pulse blanking, can effectively suppress GNSS interference signals. Their performance is typically influenced by the receiver's front-end hardware parameters, placing high demands on the accuracy of the ADC and sampler. However, notch filters can rapidly attenuate the input signal at a specified frequency. For narrowband interference with a small frequency fluctuation range, they can use the tracking results from the previous moment to assist the current tracking frequency, reducing the error between the notch frequency and the actual interference frequency, thereby improving the accuracy of filtering interference signals and reducing the loss of useful signals. For narrowband interference with a large frequency fluctuation range, the notch filter needs to quickly adjust the tracking step size to ensure stable tracking of the interference signal. Furthermore, the number of interference signals also determines the number of notch filters required. Therefore, the performance parameters of notch filters to achieve satisfactory interference filtering performance vary depending on the characteristics of different interference signals. However, notch filters typically use fixed performance parameters, and such notch filtering techniques are often only applicable to specific types of interference signals.

[0053] However, the types of interference signals in real-world environments are often unknown and change randomly. Research on how to enable a single-antenna receiver to autonomously monitor the interference environment and suppress its effects in unknown interference environments is still insufficient.

[0054] This invention addresses the problem of poor anti-interference capability in existing single-antenna GNSS receivers by proposing a method and system for GNSS signal interference monitoring and suppression based on joint differential spectral density (DSD) and notch filtering techniques. This invention explores its application in the field of GNSS anti-interference. Primarily targeting the intermediate frequency (IF) signal acquired by the GNSS receiver front-end, it detects interference signals and identifies the interference type based on the differential cumulative energy spectrum (DCSP) of the IF signal. The identified information is then fused to dynamically adjust the notch filter parameters, filtering the interference signal in the IF signal and suppressing it. By evaluating the notch filtering effect and dynamically monitoring changes in the interference environment, a complete and independent anti-interference scheme integrating GNSS interference detection, identification, and adaptive suppression is achieved. Without altering the receiver's internal structure, this method utilizes simple modules and minimal computation to achieve dynamic sensing and suppression of interference signals by a single-antenna receiver, significantly improving its anti-interference capability. In addition, the filtered signal is input to the receiver correlator for subsequent signal processing, ensuring the functional independence of the receiver front-end, interference detection module and receiver correlator, so as to avoid mutual interference between the various functional modules and ensure the accuracy and stability of the system.

[0055] Exemplary methods

[0056] This invention provides a method for monitoring and suppressing interference in GNSS signals, which is deployed on a single-antenna receiver, but is not limited to this. It can also be deployed on other electronic devices that can receive GNSS signals, such as mobile phones, smart wearable products, navigators, computers, servers, microcontrollers, and microcontrollers. The method is aimed at detecting, identifying, and suppressing interference in a single-antenna GNSS receiver.

[0057] The structure of the single-antenna receiver in this embodiment is as follows: Figure 1 As shown, the system includes an antenna module, a GNSS signal interference monitoring and suppression system, and a power supply. The GNSS signal interference monitoring and suppression system includes a receiver front-end preprocessing unit, a switching module, a DCSP interference warning unit, a DCSP interference identification unit, a parameter matching notch filter unit, a filter evaluation and optimization unit, and a receiver correlator. The receiver front-end preprocessing unit has one input and one output, the switching module has three inputs and two outputs, the DSCP interference warning module has one input and two outputs, the DCSP interference identification unit has one input and one output, the parameter matching notch filter unit has two inputs and two outputs, the filter evaluation and optimization unit module has one input and two outputs, and the receiver correlator has two inputs. Signals emitted by navigation satellites and jammers are received by the receiver front-end preprocessing unit. The preprocessing unit processes the received signals to obtain an intermediate frequency (IF) signal. This IF signal data is input to the first input terminal of the switching module. The first output terminal of the switching module is connected to the input terminal of the DCSP interference warning unit. The first output terminal of the DCSP interference warning unit outputs a no-interference alarm and the raw IF data, which is then input to the first input terminal of the receiver correlator. The second output terminal of the DCSP interference warning unit outputs interference warning information, which is input to the input terminal of the DCSP interference identification unit. The output terminal of the DCSP interference warning unit outputs the interference type and interference signal. The characteristic parameters are input to the first input terminal of the parameter matching notch filter unit. The first output terminal of the parameter matching notch filter unit outputs the filtered data and inputs it to the second input terminal of the receiver correlator. The second output terminal of the parameter matching notch filter unit outputs the signal at the notch frequency, i.e. the filtered signal, and inputs it to the input terminal of the filter evaluation and optimization unit. The first output terminal of the filter evaluation and optimization unit outputs the invalid filter and inputs it to the second input terminal of the switching module. The second output terminal of the filter evaluation and optimization unit outputs the valid filter and inputs it to the third input terminal of the switching module. At the same time, the third input terminal of the switching module is connected to the second input terminal of the parameter matching notch filter unit.

[0058] The receiver front-end preprocessing unit is used to obtain the intermediate frequency signal based on the received GNSS signal.

[0059] The DCSP interference warning unit is used to perform spectrum estimation on the intermediate frequency signal to obtain the differential cumulative power spectrum of the intermediate frequency signal; if the differential cumulative power spectrum of the intermediate frequency signal exceeds the preset differential cumulative power spectrum threshold, an interference warning signal is issued.

[0060] The DCSP interference identification unit is used to obtain the characteristic parameters of the interference signal by using the differential cumulative power spectrum based on the warning information of the DCSP interference warning mode.

[0061] The parameter matching notch filter unit is used to set the notch frequency according to the characteristic parameters of the identified interference signal, and to filter the intermediate frequency signal based on the notch frequency to obtain the target signal and the filtered signal.

[0062] The filter evaluation and optimization unit is used to evaluate the filtered signal based on the signal energy. When the evaluation of the filtered signal is invalid, the notch frequency is readjusted and the filtering process is repeated to obtain the updated target signal and output the updated target signal. When the evaluation of the filtered signal is valid, the target signal is output.

[0063] The single-antenna receiver in this embodiment can effectively detect interference signals and identify the type of interference. It then fuses the identified information to dynamically adjust the notch filter parameters, filtering the interference signals in the intermediate frequency signal to suppress them. Furthermore, by evaluating the notch filter effect, it dynamically monitors changes in the interference environment. Therefore, this single-antenna receiver, without altering the internal structure of the receiver, achieves dynamic sensing and suppression of interference signals through simple modules and minimal computation, significantly improving the anti-interference capability of a single-antenna GNSS receiver.

[0064] The GNSS signal interference monitoring and suppression system in the aforementioned single-antenna receiver is used to implement a method for GNSS signal interference monitoring and suppression. The flowchart of this method is as follows: Figure 2 As shown, the main steps include:

[0065] Step S100: Obtain the intermediate frequency signal based on the received GNSS signal.

[0066] Specifically, GNSS signals transmitted by navigation satellites and jamming signals transmitted by jammers are received by the antenna and processed by the receiver front end to obtain intermediate frequency (IF) data. The IF data is then input to the switching module, which is initially set to a closed invalid switch and an open valid switch.

[0067] When the invalid switch of the switching module is closed and the valid switch is open, the switching module inputs a null value to the parameter matching notch filter unit and simultaneously inputs an intermediate frequency signal to the DCSP interference warning module.

[0068] Step S200: Perform spectral estimation on the intermediate frequency signal to obtain the differential cumulative power spectrum of the intermediate frequency signal.

[0069] Step S300: If the differential cumulative power spectrum of the intermediate frequency signal exceeds the preset differential cumulative power spectrum threshold, an interference warning signal is issued, and the characteristic parameters of the interference signal are obtained using the differential cumulative power spectrum.

[0070] Specifically, the DCSP interference warning module compares the DCSP array of the intermediate frequency (IF) signal with a preset threshold. If the DCSP is below the threshold, no interference alarm is triggered, and the IF signal is directly input to the receiver correlator module for related processing. If the DCSP value exceeds the preset threshold, i.e., interference is detected, an interference alarm is triggered, and the IF signal and DCSP array are input to the DCSP interference identification module for processing. That is, based on the differential cumulative power spectrum of the IF signal and the preset differential cumulative power spectrum threshold, it determines whether interference exists. If the differential cumulative power spectrum of the IF signal exceeds the preset differential cumulative power spectrum threshold, it is determined that interference exists and an interference warning signal is issued. Then, the characteristic parameters of the interference signal are obtained using the differential cumulative power spectrum.

[0071] Step S400: Set the notch frequency according to the characteristic parameters of the interference signal, and filter the intermediate frequency signal based on the notch frequency to obtain the target signal and the filtered signal.

[0072] Specifically, the initial notch frequency is set to be the same as the frequency of the interference signal based on the characteristic parameters of the interference signal. This filters out the frequency components corresponding to the interference signal, obtaining the filtered intermediate frequency signal (i.e., the target signal) and the signal corresponding to the set notch frequency (i.e., the filtered signal). It should be noted that in actual receiver use, the current notch frequency may be the updated frequency for this use, or it may be the effective notch frequency corresponding to the previous filtering. It may not be effective for the current filtering process. Therefore, an evaluation is needed during the filtering effect assessment stage, and the notch frequency may need to be updated if necessary.

[0073] Step S500: Evaluate the filtered signal based on the signal energy. If the evaluated filtered signal is invalid, re-identify the interference signal characteristic parameters in steps S200 and S300. Adjust the notch frequency based on the updated interference signal characteristic parameters and re-filter the intermediate frequency signal until the evaluated filtered signal is valid. If the evaluated filtered signal is valid, output the target signal.

[0074] This embodiment can not only issue a warning when interference signals are detected, but also automatically identify the type of interference. Furthermore, when the filtering effect is detected to be ineffective, it can determine the change in the type of interference signal and adjust the filtering frequency in a timely manner. This enables dynamic detection and identification of interference signals in the environment, as well as adjustment of the notch filter frequency, to ensure that interference signals are effectively detected and adaptively suppressed, thereby improving the anti-interference performance of the single-antenna GNSS receiver in various interference environments.

[0075] In one implementation, spectral estimation is performed on the intermediate frequency signal in step S200 to obtain the differential cumulative power spectrum of the intermediate frequency signal, specifically including:

[0076] Step S210: Obtain the power spectral density of the intermediate frequency signal, integrate and normalize the power spectral density to obtain the normalized cumulative spectral density;

[0077] Specifically, the DCSP interference early warning module obtains the DCSP value of the intermediate frequency (IF) data through spectral estimation, normalization, and differential processing. The estimation process of the DSCP value is as follows:

[0078] The signal r(t) received by the receiver antenna at time t is actually the satellite signal s. i The superposition effect of thermal noise η(t) and potential interference signal J(t) can be expressed by formula (1), that is:

[0079]

[0080] Where L is the total number of visible satellites, and δ(t) is the interference flag. δ(t) = 0 means the system is unaffected by interference, and δ(t) = 1 means the system is affected by interference signals. The process of the antenna and front-end receiver processing the received signal to obtain intermediate frequency data is approximately a linear system, whose transfer function is represented by h(t).

[0081] The power spectral density of the received signal can be estimated using linear estimation methods such as autocorrelation estimation, autocovariance method, and periodogram method, or nonlinear estimation methods such as maximum likelihood method and maximum entropy method. Taking the periodogram method as an example, the signal... The power spectral density S(f) is expressed by formula (2), that is:

[0082]

[0083] in The Fourier transform is used, where N is the total length of the data sequence used for power spectrum estimation, L is the total number of visible satellites in the received signal, and n represents the time series.

[0084] Similarly, the power spectral density J(f) and transfer function H(f) of the interference signal are estimated. Since the noise signal is stationary, its power spectrum can be represented by a constant N0. Therefore, the power spectral density PSD(f) of the intermediate frequency data is expressed by formula (3), i.e.:

[0085] PSD(f)=S(f)|H(f)| 2 +N0|H(f)| 2 +δJ(f)|H(f)| 2 (3)

[0086] Integrating and normalizing the signal PSD yields the normalized cumulative spectral density CSP. norm (f), expressed by formula (4), that is:

[0087]

[0088] Among them, f s This refers to the sampling frequency at the receiver front end.

[0089] Step S220: Based on the normalized cumulative spectral density and the preset cumulative spectral density reference value, obtain the differential cumulative power spectrum of the intermediate frequency signal.

[0090] Specifically, a reference value CSP is defined based on the cumulative spectral density of a normal intermediate frequency signal. ref (f) can be expressed by formula (5), that is:

[0091]

[0092] Due to the defined reference value CSP ref (f) depends only on the receiver front-end characteristics H(f) and is not affected by the signal magnitude. Therefore, the differential cumulative power spectrum DCSP(f) is expressed by formula (6), that is:

[0093] DCSP(f) = CSP norm (f)-CSP ref (f) (6)

[0094] In one embodiment, the step of determining the differential cumulative power spectrum threshold in step S300 includes:

[0095] Step S310: Obtain historical data of GNSS signals, and based on the historical data of GNSS signals, obtain the fluctuation range of the differential cumulative power spectrum of the intermediate frequency signal;

[0096] Specifically, statistical analysis of the receiver's normal historical GNSS signal data at different dates and times ensures that the fluctuation range of the differential cumulative power spectrum of the obtained intermediate frequency signal can more comprehensively and reasonably represent the patterns and characteristics of the historical normal GNSS signal data, thus laying a good foundation for accurate detection of interference signals in the future.

[0097] Step S320: Based on the fluctuation range of the differential cumulative power spectrum of the intermediate frequency signal, obtain the mean and variance of the differential cumulative power spectrum, and determine the threshold value of the differential cumulative power spectrum based on the mean and variance.

[0098] Specifically, if the differential cumulative power spectrum of the intermediate frequency signal exceeds a preset differential cumulative power spectrum threshold, an interference warning signal is issued. The interference decision algorithm is as follows:

[0099] Since the satellite signal power is much smaller than the floor noise, the influence of the satellite signal power spectrum is ignored. Therefore, the differential power spectrum DCSP(f) of the normal signal can be expressed by formula (7), namely:

[0100]

[0101] It can be seen that in an interference-free environment, the differential power spectrum DCSP(f) of the normal signal fluctuates around 0; in an interference environment, the power level of the interference signal is comparable to or even higher than the noise level, and cannot be ignored. Therefore, considering the power of the interference signal, the expression for the differential power spectrum DCSP(f) of the interfered intermediate frequency signal is given by formula (8), that is:

[0102]

[0103] It can be seen that the differential power spectrum DCSP(f) of the interfered intermediate frequency signal is much greater than 0.

[0104] Taking into account the characteristics of the differential power spectrum (DCSP) of the intermediate frequency signal under both interference and non-interference conditions, this embodiment uses hypothesis testing to obtain an interference warning criterion based on DCSP, which is expressed by formula (9):

[0105]

[0106] Wherein, H0 represents the null hypothesis, indicating that the received signal is not affected by the interference signal and the DCSP interference warning module does not issue an interference alarm; H1 represents the opposing hypothesis, indicating that there is an interference signal in the received signal and the DCSP interference warning module issues an interference alarm.

[0107] Based on the normal historical GNSS data received by the single-antenna receiver, the fluctuation range of the differential power spectrum (DCSP(f)) of the intermediate frequency signal of the normal signal is statistically obtained, and the threshold value λ of the differential cumulative power spectrum is determined according to the mean and variance of the differential power spectrum (DCSP(f)). th (f) is obtained by using the differential power spectrum DCSP(f) of the intermediate frequency signal under the current environment and the threshold value λ. th (f) Compare and make an interference decision. The decision rule is expressed by formula (10), namely:

[0108]

[0109] It can be seen that if the differential power spectrum DCSP(f) of the intermediate frequency signal under the current environment is less than or equal to the threshold value λ th If (f), it means that the received signal is not affected by the interference signal, and the DCSP interference warning module will not issue an interference alarm; if the differential power spectrum DCSP(f) of the intermediate frequency signal in the current environment is greater than the threshold value λ, it indicates that the received signal is not affected by the interference signal, and the DCSP interference warning module will not issue an interference alarm. th (f) indicates that there is an interference signal in the received signal. The DCSP interference warning module issues an interference alarm to remind the staff that there is interference in the current environment, and further determines the type of interference signal and adjusts the display frequency of the parameter matching notch filter unit.

[0110] In one implementation, step S300 utilizes the differential cumulative power spectrum to obtain characteristic parameters of the interference signal, specifically including:

[0111] Step S330: Collect parameters and types of several existing interference signals in advance, and based on the parameters and types of each existing interference signal, establish differential cumulative power spectrum models of the existing interference signals to obtain a model database;

[0112] Specifically, known interference signals are collected in advance. It should be noted that the known interference signals here refer to several common interference signals, such as continuous waves, multi-frequency continuous waves, and frequency sweep wave interference. Using the characteristic parameters of different types of existing interference signals, differential cumulative power spectrum models of various interference signals are established in the interference identification module according to the parameters and types of the interference signals, and a model database is obtained.

[0113] Step S340: Extract the characteristic parameters of the differential cumulative power spectrum, and use the characteristic parameters of the differential cumulative power spectrum and the differential cumulative power spectrum model of each existing interference signal to obtain the characteristic parameters of the interference signal.

[0114] Specifically, since the differential power spectrum (DCSP(f)) of different interference signals has different characteristics at a fixed frequency point, the type and characteristic parameters of the interference signal in the current environment can be obtained by comparing the characteristic parameters of the differential power spectrum (DCSP(f)) of the intermediate frequency signal input to the DCSP interference identification unit with the differential cumulative power spectrum model of each existing interference signal.

[0115] It should be noted that the characteristic parameters used in constructing the differential cumulative power spectrum model of existing interference signals refer to the characteristic parameters of common types of interference signals obtained from historical data. These are common to this type of interference signal and often represent an interval consisting of some continuous or discontinuous point values. However, the type and characteristic parameters of the interference signal obtained by comparing the characteristic parameters of the differential power spectrum DCSP(f) of the intermediate frequency signal with the constructed model refer to the characteristic parameters of the interference signals included in the intermediate frequency signal in the current environment. These are a value of the characteristic parameter of this type of interference signal, which is included in the above-mentioned interval.

[0116] For example, Figure 3 The figure shows DCSP models for several common interference signals, where B represents the single-sided bandwidth of the receiver front end. J Indicates the interference bandwidth, f J The x-axis represents the interference power, the y-axis represents the frequency, and the y-axis represents the differential power spectrum of various interference signals.

[0117] First, the following criteria are used to identify continuous wave interference, multi-frequency continuous wave interference, and frequency sweep wave interference, respectively. The specific criteria are as follows:

[0118] When the interference signal is a continuous wave interference, it satisfies f mx -f mn =Δf, Where Δf is the frequency interval, f mx Take the interference frequency corresponding to the maximum value of its DCSP; f mn Find the interference frequency corresponding to the minimum value of its DCSP, f s Where N is the sampling frequency and N is the number of sampling points;

[0119] When the interference signal is a frequency sweep wave interference, it satisfies f mx -f mn >Δf, And B J =(f mx -f mn ) / 2 < B, where, For DCSP(f) in [f mx f mn The first derivative within the frequency band, where B represents the single-sided bandwidth of the receiver front end. J This indicates the interference bandwidth.

[0120] When the interference signal is a frequency sweep wave interference, it satisfies f mx -f mn >2B>Δf, And B J ≥(f mx -f mn ) / 2>B.

[0121] When the interference signal is a multi-frequency continuous wave interference, it satisfies f mx -f mn >Δf, f mx,i -f mn，i =Δf, where f mx，i For [f mn f mx ](or [f mx f mn The interference frequency corresponding to the maximum DCSP value within the frequency band, f mn,i For [f mn f mx ](or [f mx f mn The interference frequency corresponding to the minimum DCSP value within the frequency band.

[0122] Then, by comparing the extracted DCSP feature parameters of the GNSS signal with the DCSP model of the interference signal in the database of the DCSP interference identification unit, interference type identification is achieved. It can be seen that the feature parameters involved in this implementation include f mx f mn ;、f mx，i f mn，i and wait.

[0123] from Figure 3 As can be seen, the differential power spectra of swept waves, continuous waves, and multi-frequency continuous waves are significantly different within a 2B bandwidth, making them relatively easy to identify.

[0124] In one implementation, if the pre-established differential cumulative power spectrum models of each existing interference signal do not match the type of the interference signal, then after obtaining the characteristic parameters of the interference signal, the method further includes:

[0125] Based on the characteristic parameters of the interference signal, the type of interference signal is determined; based on the characteristic parameters and type of the interference signal, a differential cumulative power spectrum model of the interference signal is constructed, and the model database is updated.

[0126] It is evident that if a differential cumulative power spectrum (DCSP) model corresponding to the type of interference signal in the current environment is not pre-established, then the type of interference signal should first be identified using its characteristic parameters. Then, using the type and characteristic parameters, a DCSP model for that interference signal can be constructed. This allows for the updating and expansion of a pre-established model database composed of several existing interference signal DCSP models, improving the efficiency of future interference signal identification. Therefore, this invention uses the DCSP model to identify interference signals. By expanding the model database, it can be applied to more complex interference environments, demonstrating strong scalability.

[0127] In one embodiment, the characteristic parameters of the interference signal in step S400 include at least the interference signal frequency and the number of interference signals. An adaptive notch filter is used to filter the intermediate frequency signal. The notch frequency is set according to the characteristic parameters of the interference signal, and the intermediate frequency signal is filtered based on the notch frequency to obtain the target signal and the filtered signal. Specifically, this includes:

[0128] Step S410: Set the number of adaptive notch filters based on the number of interference signals;

[0129] Step S420: Adjust the initial notch frequency of the adaptive notch filter based on the frequency of the interference signal;

[0130] Step S430: Filter the intermediate frequency signal based on the initial notch frequency of each adaptive notch filter to obtain the target signal and the filtered signal.

[0131] Specifically, the parameter-matching notch filter unit sets the corresponding processing parameters and number of notch filters according to the identified interference type and characteristic parameters of the interference signal, and processes the original intermediate frequency signal data to obtain the filtered target signal. Simultaneously, the filtered signal is input to the filtering evaluation and optimization unit. The parameter-matching notch filter unit includes an adaptive limiter and uses an adaptive notch filter to filter the interference signal. The transfer function of the adaptive notch filter is shown in formula (11), i.e.:

[0132]

[0133] Where z is the Z-transform operator, r determines the notch filter bandwidth, typically ranging from 0.95 to 1. The coefficient α is the cosine of the notch filter frequency, and the unit of the notch filter frequency is radians. When the sampling frequency is f... s At that time, the notch frequency f stop =f s arccos(α) / 2π, in Hz. Therefore, the frequency of the interference signal can be adaptively tracked by updating α in the transfer function of the notch filter. Let the updated value of α obtained at time n be denoted as... The update process of α is shown in formula (12), that is:

[0134]

[0135] Where x[n] = r[n] / D(z) is the intermediate parameter of the notch filter, that is, the signal component corresponding to the notch frequency; c[n] is the smoothed notch frequency f. stop The signal component at the location; d[n] represents the notch frequency f. stop The energy of the signal component at a given point is the energy of the filtered signal removed by the notch filter; n is the time series. γ is the forgetting factor, and λ is the smoothing factor. Since different choices of forgetting and smoothing factors have varying effects on the tracking and filtering of interference signals, they will also affect the final interference suppression effect.

[0136] For example, such as Figure 4 The figure shows the signal-to-noise ratio (SNR) of the target signal obtained by setting different values ​​for parameters γ and λ during the filtering process in a continuous wave interference environment. Figure 4 It is evident that the closer the parameters γ and λ are to 1, the higher the signal-to-noise ratio of the target signal obtained after filtering out the continuous wave, meaning the better the filtering effect of the notch filter. Similarly, other types of interference can be modeled and analyzed in a similar manner. By adjusting the values ​​of parameters γ and λ, the parameter range corresponding to the optimal filtering effect can be obtained.

[0137] Therefore, based on the identified interference type and parameters, the adaptive filter is configured with parameters matching the interference type: the initial notch frequency of the notch filter is set according to the frequency of the interference signal; the number of notch filters is set according to the quantity of interference signals; and the optimal forgetting factor and smoothing factor parameters are selected based on their impact on the quality of the filtered signal. In this embodiment, the signal-to-noise ratio is used to evaluate the filtering effect. As another preferred implementation, other indicators can also be selected for evaluation.

[0138] In one implementation, in step S500, when the evaluated filtered signal is invalid, the interference signal characteristic parameters are re-identified through step S300, the notch filter frequency is adjusted, and the intermediate frequency signal is re-filtered until the evaluated filtered signal is valid; when the evaluated filtered signal is valid, the target signal is output, specifically including:

[0139] If the difference between the energy of the filtered signal and the energy of the standard GNSS signal is less than or equal to a preset energy threshold, the notch frequency is adjusted in real time, and the filtering process on the intermediate frequency signal before the first filtering is repeated to obtain the updated target signal. Then, the effectiveness of the filtering is evaluated based on the updated target signal. If it is ineffective, the notch frequency is adjusted and the filtering process is repeated until the evaluation is effective, and then the updated target signal is output. If the difference between the energy of the filtered signal and the energy of the standard GNSS signal is greater than a preset energy threshold, the target signal is output.

[0140] Specifically, the effectiveness of the filtering process is verified by checking the frequency of the filtered signal. The evaluation algorithm is as follows:

[0141] First, extract the intermediate parameter d[n] of the notch filter in formula (12), which represents the notch filter frequency f. stop The signal energy at that location is the energy of the signal that has been filtered out by the notch filter.

[0142] When f stop When there is an interference signal, the filtered signal is the interference signal. The notch filter successfully filters out the interference signal. The filtered signal is input into the correlator for processing. At the same time, the notch filter continuously tracks and filters out the interference signal.

[0143] When f stop When there is no interference signal, the filtered signal is a normal signal. At this time, the filtering effect of the notch filter is invalid. The useful signal is filtered out, and the original intermediate frequency signal is input to the correlator for processing and calculation. This means that the interference environment has changed. The interference warning and identification module re-detects and identifies the interference of the intermediate frequency signal and resets the notch filter parameters.

[0144] Then, based on empirical data, the normal signal at f is obtained. stop Standard energy E at the location ref The filtering effect is evaluated using hypothesis testing, and the corresponding evaluation criteria are shown in formula (13), namely:

[0145]

[0146] As can be seen, when the notch filter effectively filters out interference, since the power of the interference signal is much greater than that of the navigation signal, d[n] >> E. ref When the notch filter is ineffective, the energy level of the filtered normal signal is equivalent to the energy standard, i.e., d[n]≈E. ref .

[0147] When the filter evaluation and optimization unit determines that the filter is effective, the switching module keeps the invalid switch open and the effective switch closed. The filtered data from the notch filter is input to the receiver correlator for further processing. Simultaneously, the intermediate frequency (IF) data for the next moment is directly input to the parameter-matching notch filter unit via the switching module. When the filter evaluation and optimization unit determines that the filter is ineffective, indicating a change in the interference environment, the switching module switches to the invalid switch closed and the effective switch open. The parameter-matching notch filter unit inputs the original IF data to the receiver correlator for processing. Simultaneously, after readjusting the notch frequency based on the IF data for the next moment, the filtering process is repeated to obtain and output the updated target signal for re-interference monitoring and identification, ensuring effective suppression of interference signals within the receiver. By dynamically and specifically adjusting the notch filter parameters according to the interference type, the loss to normal signals is reduced, avoiding the problem that traditional filters can only handle a single type of interference, thus improving the notch filter's anti-interference performance. Furthermore, the evaluation and optimization unit provides feedback on the filtering effect, enabling dynamic monitoring of the GNSS interference environment and notch interference adjustment, which is of greater practical significance.

[0148] In summary, this invention not only issues early warnings when interference signals are detected, but also automatically identifies the type of interference. Furthermore, when filtering is found to be ineffective, it determines changes in the type of interference signal and adjusts the filtering frequency accordingly. This enables dynamic detection and identification of interference signals in the environment, as well as adjustment of the notch filter frequency, ensuring effective detection and suppression of interference signals. Consequently, it improves the anti-interference performance of single-antenna GNSS receivers against various interference environments. Therefore, this invention, employing a simple combination of differential spectral analysis and notch filtering, achieves detection, identification, and adaptive suppression of various interference environments with low computational load and low hardware cost, possessing significant engineering and application value.

[0149] In addition, the system corresponding to this invention only needs to perform analog-to-digital conversion on the received GNSS signal at the front end, and then realize various processing functions between the intermediate frequency and the baseband. It does not require changing the internal structure of the receiver signal processing, making engineering implementation simple. Moreover, it is not affected by the structure and parameters of navigation satellite signals, and can be applied to various satellite navigation systems such as GPS and Beidou, making it highly versatile.

[0150] Corresponding to the above-mentioned method for monitoring and suppressing interference of GNSS signals, this embodiment of the invention also provides a single-antenna anti-interference receiver. The single-antenna anti-interference receiver stores a program for monitoring and suppressing interference of GNSS signals. When the program for monitoring and suppressing interference of GNSS signals is executed by a processor, it implements the steps of the above-mentioned method for monitoring and suppressing interference of GNSS signals.

[0151] This invention also provides a computer-readable storage medium storing a GNSS signal interference monitoring and suppression program. When the GNSS signal interference monitoring and suppression program is executed by a processor, it implements the steps of any of the GNSS signal interference monitoring and suppression methods provided in this invention.

[0152] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0153] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is merely an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the above device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiments can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit. Furthermore, the specific names of the functional units and modules are only for easy differentiation and are not intended to limit the scope of protection of this invention. The specific working process of the units and modules in the above system can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0154] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0155] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0156] In the embodiments provided by this invention, it should be understood that the disclosed apparatus / terminal devices and methods can be implemented in other ways. For example, the apparatus / terminal device embodiments described above are merely illustrative. For instance, the division of the above modules or units is merely a logical functional division, and in actual implementation, it can be divided in other ways. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed.

[0157] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not mean that the essence of the corresponding technical solutions deviates from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included within the protection scope of the present invention.

Claims

1. A method for monitoring and suppressing interference in GNSS signals, characterized in that, Includes the following steps: Based on the received GNSS signal, the intermediate frequency signal is obtained; The intermediate frequency signal is subjected to spectral estimation to obtain the differential cumulative power spectrum of the intermediate frequency signal; If the differential cumulative power spectrum of the intermediate frequency signal exceeds a preset differential cumulative power spectrum threshold, an interference warning signal is issued, and the characteristic parameters of the interference signal are obtained using the differential cumulative power spectrum. The notch frequency is set according to the characteristic parameters of the interference signal, and the intermediate frequency signal is filtered based on the notch frequency to obtain the target signal and the filtered signal. The filtered signal is evaluated based on its energy. If the evaluated filtered signal is invalid, the characteristic parameters of the interference signal are re-identified, the notch filter frequency is adjusted, and the intermediate frequency signal is re-filtered until the evaluated filtered signal is valid. If the evaluated filtered signal is valid, the target signal is output. The process of obtaining characteristic parameters of the interference signal using the differential cumulative power spectrum includes: Parameters and types of several existing interference signals are collected in advance, and differential cumulative power spectrum models of existing interference signals are established based on the parameters and types of each existing interference signal to obtain a model database; The characteristic parameters of the differential cumulative power spectrum are extracted, and the characteristic parameters of the interference signal are obtained by using the characteristic parameters of the differential cumulative power spectrum and the differential cumulative power spectrum model of each of the existing interference signals; If the pre-established differential cumulative power spectrum models of each of the existing interference signals do not match the type of the interference signal, then after obtaining the characteristic parameters of the interference signal, the process further includes: Based on the characteristic parameters of the interference signal, the type of interference signal is determined; Based on the characteristic parameters and type of the interference signal, a differential cumulative power spectrum model of the interference signal is constructed, and the model database is updated.

2. The method for monitoring and suppressing interference in GNSS signals according to claim 1, characterized in that, The step of performing spectral estimation on the intermediate frequency signal to obtain the differential cumulative power spectrum of the intermediate frequency signal includes: The power spectral density of the intermediate frequency signal is obtained, and the power spectral density is integrated and normalized to obtain the normalized cumulative spectral density. Based on the normalized cumulative spectral density and the preset cumulative spectral density reference value, the differential cumulative power spectrum of the intermediate frequency signal is obtained.

3. The method for monitoring and suppressing interference in GNSS signals according to claim 1, characterized in that, The step of determining the differential cumulative power spectrum threshold includes: Historical data of GNSS signals are acquired, and based on the historical data of GNSS signals, the fluctuation range of the differential cumulative power spectrum of the intermediate frequency signal is obtained; Based on the fluctuation range of the differential cumulative power spectrum of the intermediate frequency signal, the mean and variance of the differential cumulative power spectrum are obtained, and based on the mean and variance, the threshold value of the differential cumulative power spectrum is determined.

4. The method for monitoring and suppressing interference in GNSS signals according to claim 1, characterized in that, The characteristic parameters of the interference signal include at least the interference signal frequency and the number of interference signals. An adaptive notch filter is used to filter the intermediate frequency signal. The process of setting the notch frequency based on the characteristic parameters of the interference signal and filtering the intermediate frequency signal based on the notch frequency to obtain the target signal and the filtered signal includes: The number of adaptive notch filters is set based on the number of interference signals. Based on the frequency of the interference signal, adjust the initial notch frequency of the adaptive notch filter; The intermediate frequency signal is filtered based on the initial notch frequency of each of the adaptive notch filters to obtain the target signal and the filtered signal.

5. The method for monitoring and suppressing interference in GNSS signals according to claim 1, characterized in that, Evaluating the effectiveness of the filtered signal includes: If the difference between the energy of the filtered signal and the energy of the standard GNSS signal is less than or equal to a preset energy threshold, the filtered signal is determined to be invalid; otherwise, the filtered signal is determined to be valid.

6. A GNSS signal interference monitoring and suppression system, characterized in that, The system includes: The receiver front-end preprocessing unit is used to obtain the intermediate frequency signal based on the received GNSS signal; The DCSP interference warning unit is used to perform spectrum estimation on the intermediate frequency signal to obtain the differential cumulative power spectrum of the intermediate frequency signal; if the differential cumulative power spectrum of the intermediate frequency signal exceeds a preset differential cumulative power spectrum threshold, an interference warning signal is issued. The DCSP interference identification unit is used to obtain the characteristic parameters of the interference signal based on the warning information from the DCSP interference warning unit and the differential cumulative power spectrum. The parameter matching notch filter unit is used to set the notch frequency according to the characteristic parameters of the interference signal, and to filter the intermediate frequency signal based on the notch frequency to obtain the target signal and the filtered signal. The filtering evaluation and optimization unit is used to evaluate the filtered signal based on the signal energy. When the evaluation of the filtered signal is invalid, the characteristic parameters of the interference signal are re-identified, the notch frequency is adjusted, and the intermediate frequency signal is re-filtered until the evaluated filtered signal is valid. When the evaluation of the filtered signal is valid, the target signal is output. The process of obtaining characteristic parameters of the interference signal using the differential cumulative power spectrum includes: Parameters and types of several existing interference signals are collected in advance, and differential cumulative power spectrum models of existing interference signals are established based on the parameters and types of each existing interference signal to obtain a model database; The characteristic parameters of the differential cumulative power spectrum are extracted, and the characteristic parameters of the interference signal are obtained by using the characteristic parameters of the differential cumulative power spectrum and the differential cumulative power spectrum model of each of the existing interference signals; If the pre-established differential cumulative power spectrum models of each of the existing interference signals do not match the type of the interference signal, then after obtaining the characteristic parameters of the interference signal, the process further includes: Based on the characteristic parameters of the interference signal, the type of interference signal is determined; Based on the characteristic parameters and type of the interference signal, a differential cumulative power spectrum model of the interference signal is constructed, and the model database is updated.

7. A single-antenna anti-interference receiver, characterized in that, The single-antenna anti-interference receiver stores a GNSS signal interference monitoring and suppression program. When the GNSS signal interference monitoring and suppression program is executed by the processor, it implements the steps of the GNSS signal interference monitoring and suppression method as described in any one of claims 1-5.

8. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a GNSS signal interference monitoring and suppression program, which, when executed by a processor, implements the steps of the GNSS signal interference monitoring and suppression method as described in any one of claims 1-5.

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