CN111092632B

CN111092632B - Interference suppression method and interference suppressor

Info

Publication number: CN111092632B
Application number: CN201911216821.8A
Authority: CN
Inventors: 戴伟; 谢明明; 杨涛; 欧阳晨曦
Original assignee: Chengdu Zhongzhitiancheng Technology Co ltd
Current assignee: Chengdu Zhongzhitiancheng Technology Co ltd
Priority date: 2019-12-03
Filing date: 2019-12-03
Publication date: 2022-04-05
Anticipated expiration: 2039-12-03
Also published as: CN111092632A

Abstract

The invention discloses an interference suppression method and an interference suppressor. The pressing method comprises the following steps: the method comprises the steps of pre-selection amplification, down-conversion, intermediate frequency filtering and gain control of radio frequency signals, the steps of scanning discovery, feature identification, strategy matching and interference signal generation of the signals, and the steps of filtering, up-conversion and amplification of the interference signals. Wherein the interference signal is generated in a manner imitating the adoption of the non-conventional radio frequency signal. The interference suppressor comprises a radio frequency receiving unit, a signal processing unit and a radio frequency up-conversion unit, which are implemented as hardware of the suppressing method. The invention can be used for suppressing various types of radio frequency signals; the signal receiving and the radio frequency signal generation are combined together, the discovery and tracking capacity of the target signal is effectively enhanced by adopting a mode of guiding the generation of the interference signal by the received signal, and the response speed of the system can be improved by presetting the strategy library.

Description

Interference suppression method and interference suppressor

Technical Field

The invention relates to the technical field of radio anti-interference, in particular to a signal interference suppression method adopting a guide interference mode and having multiple signal imitations and an interference suppressor with the same principle.

Background

With the rapid development of modern communication technology and the wide application of radio technology, radio has been deeply involved in the aspects of daily life of people, and the production life style of human society is continuously changing. The legal utilization of radio technology does bring convenience to people, but if used maliciously, it poses a threat to national and social security. Therefore, in order to ensure the development of normal and legal radio application services and the security of wireless information, specific illegal radio signals need to be managed and controlled.

The control method aiming at the illegal radio signals mainly interferes the target signals in the modes of broadband interference, target interference, signal blocking and the like so as to achieve the purpose of blocking the communication of the target signals. Broadband interference is primarily spectral coverage interference at a target frequency by a broadband swept frequency or a large bandwidth FM (frequency modulated) signal. The frequency sweep range is wide, the pertinence to a target signal is relatively weak, and therefore the interference blocking efficiency is relatively low; the targeted interference mainly aims at the specific target signal and adopts the noise signal interference of the same frequency and the same modulation, and has better interference effect compared with the conventional communication signal. However, if a target signal is subjected to complex communication modes such as frequency hopping, frequency hopping and spreading, ultra-wideband and the like, the change of the target frequency is difficult to track in time by the method, and the target signal cannot be interfered effectively; the signal blocking is to block the normal communication reception by a high-power radio frequency signal, so that the signal to noise ratio of the communication signal is deteriorated and the normal communication cannot be performed. The mode has higher manufacturing cost relative to equipment and limited interference effect on digital communication signals.

Most signal interference equipment in the market at present has the working principle that the frequency domain and the modulation domain of a radio frequency signal are interfered by a high-power radio frequency signal which is transmitted and modulated at the same frequency as the radio frequency signal. The interference control mode is more suitable for illegal signal control by adopting a conventional communication mode, the signal communication mode and the signal modulation are relatively easy to identify and simulate, interference is carried out by the same frequency and the same modulation noise, and the interference blocking effect is relatively obvious. However, for some illegal frequency-use signals using unconventional modulation signals, because the signals adopt a self-defined mode in a communication mode, signal modulation, channel coding and the like, or adopt complex communication modes such as frequency hopping, spread spectrum, frequency hopping spread spectrum and the like, the signal characteristics of the signals have great difference from those of the conventional signal communication signals, and the relative anti-interference capability is stronger, for example: various cheating signals of Sanlipu series, NF series and cloud X series. Therefore, it is difficult to achieve an ideal control effect by using a conventional interference control method.

In order to adapt to the management and control requirements of various conventional or non-conventional signals and better improve the management and control signal range and effect of the management and control equipment, a scheme for suppressing radio frequency signals of non-conventional signal types is needed.

Disclosure of Invention

The invention aims to: in view of the existing problems, the invention provides an interference suppression method based on a signal imitation mode and a corresponding interference suppressor. Aiming at the problem that the interference control effect of a conventional interference suppression source on complex communication signals and unconventional communication signals is not ideal, the signal interference blocking signal generation in a complex communication mode or a custom communication mode is mainly solved.

The technical scheme adopted by the invention is as follows:

a disturbance suppression method comprising the steps of:

A. converting the received radio frequency signal into a broadband intermediate frequency signal of a target frequency band; in the process, the signal intensity of the radio-frequency signal collected by the radio-frequency receiving unit and the signal intensity of the output broadband intermediate-frequency signal are detected in real time respectively, and the signal intensity of the collected radio-frequency signal and the signal intensity of the converted broadband intermediate-frequency signal are subjected to gain control based on the corresponding relation between the detection result, the preset detection result and the gain control strategy; the output power corresponding to the acquired radio frequency signals is ensured to be in a preset range, and the radio frequency signals with different intensities can be accurately received;

B. carrying out continuous spectrum scanning on the signal spectrum of the broadband intermediate-frequency signal to obtain each sub-signal in a target frequency band; for each sub-signal, the following steps are respectively executed:

C. judging whether the sub signal is an unconventional signal or not according to the characteristics of the sub signal, if so, executing D, wherein the unconventional signal is a signal with characteristics which cannot be identified;

D. aiming at the non-conventional signals, the communication characteristics of the sub-signals are imitated in a signal recording mode to obtain interference signals, and then the interference signals are released to suppress corresponding radio frequency signals. The corresponding radio frequency signal, namely the target signal containing the unconventional interference, suppresses the unconventional interference part.

The method mainly aims at the radio frequency signals of a complex communication mode or the radio frequency signals of a user-defined communication mode, and the signal characteristics are not easy to identify and classify, so that the reverse blocking cannot be carried out by adopting a conventional anti-interference measure. The invention adopts the mode of recording and replaying the target radio frequency signal and blocks the radio frequency signal by the interference signal matched with the self characteristic of the radio frequency signal, thereby having strong pertinence, high characteristic matching degree and ideal blocking effect. Meanwhile, due to the fact that the characteristic identification is carried out on the radio frequency signal baseband, the calculation amount and the storage amount are low. By the method, various complex radio frequency signals or custom radio frequency signals can be suppressed.

In addition, the method adopts a parallel working mode of combining radio frequency signal receiving and interference signal generating, and the received radio frequency signal is used for guiding the generation of the interference signal in real time, so that the real-time tracking and blocking of the target signal can be realized.

Further, in the step C, the method for determining whether the partial signal is an irregular signal according to the feature of the partial signal includes:

respectively acquiring characteristic parameters of the sub-signals in a time domain, a frequency domain, a modulation domain and a code domain, and judging whether the sub-signals are unconventional signals or not by comparing the characteristic parameters with a standard signal characteristic sample library;

or identifying whether the type of the sub-signal is an unconventional signal or not by using a signal classifier based on the characteristic parameters of the sub-signal in the time domain, the frequency domain, the modulation domain and the code domain, wherein the signal classifier is obtained by deeply learning the characteristic parameters of the sub-signal obtained by historical scanning in the time domain, the frequency domain, the modulation domain and the code domain and the corresponding discrimination type.

The method judges the signal type by using the main characteristic parameters of the signal, and has the characteristics of rapidness and high efficiency. By adopting the machine learning mode, signal samples can be accumulated continuously, so that the judgment and the countermeasure of the radio frequency signals are enriched continuously, and the natural optimization of the scheme is realized.

Further, the method for imitating the communication characteristics of the sub-signals in the step D comprises:

acquiring and intercepting signal data of a digital intermediate frequency signal corresponding to the branch signal within a preset time period, and then performing digital-to-analog conversion, filtering, up-conversion and amplification processing on the intercepted signal data to obtain an interference signal;

or, collecting and intercepting signal data of the sub-signal in a preset time period as an interference signal.

The digital intermediate frequency signals (corresponding to baseband signals) are intercepted, converted in an analog-to-digital mode, filtered, up-converted and amplified, so that the data storage capacity is small and the calculated amount is small. The matching degree of the two modes and the characteristics of the radio frequency signals is high, and the radio frequency signals can be blocked well.

The invention provides another interference suppression method, which comprises the following steps:

C. judging the type of the branch signal according to the characteristic of the branch signal; the sub-signal type discrimination result comprises a conventional signal and an unconventional signal;

D. matching a corresponding interference handling strategy in a preset strategy library based on the type of the binary signal discrimination; the strategy base stores signal types and corresponding interference handling strategies in a correlated manner; the interference handling policies comprise a conventional interference handling policy corresponding to a conventional signal and an irregular interference handling policy corresponding to an irregular signal;

E. generating a corresponding interference signal according to the matched interference handling strategy, wherein the method for generating the interference signal corresponds to the unconventional interference handling strategy and comprises the following steps: by means of signal recording, the signal communication characteristics are imitated to obtain interference signals, and then the interference signals are subjected to anti-interference release.

The method can deal with all types of radio frequency signals including conventional radio frequency signals, complex radio frequency signals, user-defined radio frequency signals and the like, correspondingly makes targeted anti-interference measures, and has strong pertinence, so that the method has strong response efficiency on one hand, and has good blocking effect on the radio frequency signals on the other hand.

Further, the method for imitating the communication characteristics of the sub-signals in step D to obtain the interference signals comprises:

Further, in the step C, the method for determining the type of the partial signal according to the feature of the partial signal includes:

respectively acquiring characteristic parameters of the sub-signals in a time domain, a frequency domain, a modulation domain and a code domain, and identifying the types of the sub-signals by comparing the characteristic parameters with a standard signal characteristic sample library;

or identifying the type of the sub-signal by using a signal classifier based on the characteristic parameters of the sub-signal in the time domain, the frequency domain, the modulation domain and the code domain, wherein the signal classifier is obtained by deeply learning the characteristic parameters of the sub-signal obtained by historical scanning in the time domain, the frequency domain, the modulation domain and the code domain and the corresponding discrimination type.

The invention also provides an interference suppressor, which comprises a radio frequency receiving unit, a signal processing unit and a radio frequency up-conversion unit;

the radio frequency receiving unit comprises a preselection amplification module, a down-conversion module and an intermediate frequency filtering module; the pre-selection amplification module performs pre-selection amplification on a received radio frequency signal based on a preset frequency range, the down-conversion module performs down-conversion on the pre-selected and amplified signal based on a target frequency band to obtain an intermediate frequency signal, and the intermediate frequency filtering module performs intermediate frequency filtering on the intermediate frequency signal based on a set target frequency band to obtain a corresponding broadband intermediate frequency signal; a preset frequency range, namely a frequency range required or targeted in the radio frequency signal, and a frequency band convenient for signal acquisition of a target frequency band;

the signal processing unit comprises an intermediate frequency data acquisition module, an intermediate frequency digital signal processing module, a signal analysis processing module and a gain control module; the intermediate frequency data acquisition module performs analog-to-digital conversion on the broadband intermediate frequency signal to obtain a digital intermediate frequency signal; the intermediate frequency digital signal processing module performs digital signal processing on the digital intermediate frequency signal to obtain a broadband signal frequency spectrum; the signal analysis processing module carries out continuous spectrum scanning on the signal spectrum of the broadband intermediate-frequency signal to obtain each sub-signal in a target frequency band; for each sub signal, judging whether the corresponding sub signal is an unconventional signal or not according to the characteristics of the sub signal, if so, acquiring and intercepting signal data of a digital intermediate frequency signal corresponding to the sub signal in a preset time period as a simulated signal, and performing digital-to-analog conversion on the simulated signal; the gain control module respectively detects the signal intensity of the radio-frequency signal acquired by the radio-frequency receiving unit and the signal intensity of the output broadband intermediate-frequency signal in real time, and performs gain control on the acquired radio-frequency signal and the signal intensity of the broadband intermediate-frequency signal obtained by processing based on the corresponding relation between the detection result, the preset detection result and the gain control strategy; the output power of the received radio frequency signals is ensured to be in a preset range, and the radio frequency signals with different intensities can be accurately received;

the radio frequency up-conversion unit comprises a signal filtering module, an up-conversion module and an amplification module; the signal filtering module filters the imitation signals, the imitation signals are subjected to up-conversion processing by the up-conversion module, and then the imitation signals are amplified by the amplifying module and then transmitted.

The interference suppressor is mainly used for suppressing the interference of the radio frequency signals in a complex communication mode or the radio frequency signals in a user-defined communication mode, adopts a mode of recording and replaying the radio frequency signals, and blocks the target radio frequency signals by the interference signals matched with the characteristics of the radio frequency signals, so that the pertinence is strong, the characteristic matching degree is high, and the blocking effect is ideal. Meanwhile, due to the fact that the characteristic identification is carried out on the radio frequency signal baseband, the calculation amount and the storage amount are low. Through the mode, various complex radio frequency signals or custom radio frequency signals can be suppressed.

Further, the method for judging whether the corresponding sub-signal is an unconventional signal by the signal analysis processing module according to the characteristics of the sub-signal includes:

The invention also provides another interference suppressor, which comprises a radio frequency receiving unit, a signal processing unit and a radio frequency up-conversion unit;

the radio frequency receiving unit comprises a preselection amplification module, a down-conversion module and an intermediate frequency filtering module; the pre-selection amplification module performs pre-selection amplification on a received radio frequency signal based on a preset frequency range, the down-conversion module performs down-conversion on the pre-selected and amplified signal based on a target frequency band to obtain an intermediate frequency signal, and the intermediate frequency filtering module performs intermediate frequency filtering on the intermediate frequency signal based on a set target frequency band to obtain a corresponding broadband intermediate frequency signal;

the signal processing unit comprises an intermediate frequency data acquisition module, an intermediate frequency digital signal processing module, a signal analysis processing module and a gain control module; the intermediate frequency data acquisition module performs analog-to-digital conversion on the broadband intermediate frequency signal to obtain a digital intermediate frequency signal; the intermediate frequency digital signal processing module performs digital signal processing on the digital intermediate frequency signal to obtain a broadband signal frequency spectrum; the signal analysis processing module carries out continuous spectrum scanning on the signal spectrum of the broadband intermediate-frequency signal to obtain each sub-signal in a target frequency band; for each sub signal, judging the type of the corresponding sub signal according to the characteristics of the sub signal, wherein the type of the sub signal comprises a conventional signal and an unconventional signal; matching a corresponding interference handling strategy in a preset strategy library based on the type of the binary signal discrimination; the strategy base stores signal types and corresponding interference handling strategies in a correlated manner; the interference handling policies comprise a conventional interference handling policy corresponding to a conventional signal and an irregular interference handling policy corresponding to an irregular signal; generating a corresponding interference signal according to the matched interference handling strategy; the method for generating the interference signal corresponding to the unconventional interference handling strategy comprises the following steps: simulating the communication characteristics of the sub-signals in a signal recording mode to obtain interference signals; the gain control module respectively detects the signal intensity of the radio-frequency signal acquired by the radio-frequency receiving unit and the signal intensity of the output broadband intermediate-frequency signal in real time, and performs gain control on the acquired radio-frequency signal and the signal intensity of the broadband intermediate-frequency signal obtained by processing based on the corresponding relation between the detection result, the preset detection result and the gain control strategy; the output power of the collected radio frequency signals is ensured to be in a preset range, and the radio frequency signals with different intensities can be accurately received;

the radio frequency up-conversion unit comprises a signal filtering module, an up-conversion module and an amplification module; the signal filtering module filters the interference signal, the interference signal is subjected to up-conversion processing by the up-conversion module, and then the interference signal is amplified by the amplifying module and transmitted.

The interference suppressor can suppress all types of radio frequency signals including conventional radio frequency signals, complex radio frequency signals, user-defined radio frequency signals and the like, and corresponding suppression strategies are formulated for the various types of radio frequency signals respectively, so that the response timeliness is high, and the blocking matching is good.

Further, the method for judging the type of the corresponding sub-signal by the signal analysis processing module according to the feature of the sub-signal comprises the following steps:

In summary, due to the adoption of the technical scheme, the invention has the beneficial effects that:

1. the invention can be applied to the suppression of all types of radio frequency signals, and can suppress complex communication signals such as frequency hopping, frequency hopping and spread spectrum and radio frequency signals of a user-defined communication mode in a targeted manner.

2. The invention combines signal reception and radio frequency signal generation together, adopts a mode of receiving signals to guide interference signals to generate, effectively enhances the discovery and tracking capability of target signals, and improves the real-time property of radio frequency signal generation.

3. The invention implements different interference strategies according to different target signals, and implements noise interference with same frequency, same modulation mode and same modulation degree/code rate aiming at the conventional communication signals. Aiming at special communication signals, the method completely imitates the signal communication special diagnosis to carry out interference release and influences the receiving of subsequent signals, thereby achieving the effect of blocking communication.

Drawings

The invention will now be described, by way of example, with reference to the accompanying drawings, in which:

fig. 1 is a flow chart of a method of interference suppression using signal emulation.

Fig. 2 is a flow chart of a multi-channel rf signal interference mitigation method.

Fig. 3 is a block diagram of a multi-channel rf signal interference compressor.

Fig. 4 is an embodiment of a multi-channel rf signal interference compressor.

Detailed Description

All of the features disclosed in this specification, or all of the steps in any method or process so disclosed, may be combined in any combination, except combinations of features and/or steps that are mutually exclusive.

Any feature disclosed in this specification (including any accompanying claims, abstract) may be replaced by alternative features serving equivalent or similar purposes, unless expressly stated otherwise. That is, unless expressly stated otherwise, each feature is only an example of a generic series of equivalent or similar features.

Example one

As shown in fig. 1, the present embodiment discloses a disturbance suppression method, which includes the following steps:

A. and converting the received radio frequency signal into a broadband intermediate frequency signal of a target frequency band. For the collected radio frequency signals, firstly, preselecting and amplifying, wherein the preselecting and amplifying process comprises the steps of performing preselection filtering on frequency bands outside a required frequency range in the radio frequency signals, and selecting the required frequency range for amplification; and mixing the signals subjected to pre-selection amplification, performing down-conversion to obtain intermediate frequency signals of a target frequency band, and performing intermediate frequency filtering on the intermediate frequency signals based on the set target frequency band to filter out signals outside the intermediate frequency band, so that aliasing interference of the signals outside the intermediate frequency band during intermediate frequency acquisition is avoided, and broadband intermediate frequency signals (namely baseband signals) suitable for data acquisition are obtained.

In the process, the signal intensity of the radio frequency signal and the broadband intermediate frequency signal is detected in real time, and the acquired radio frequency signal and the signal intensity of the broadband intermediate frequency signal obtained by processing are subjected to gain control based on the detection result, so that the output power of the acquired radio frequency signal is ensured to be in a preset range, and the radio frequency signals with different intensities can be accurately received. The gain control process is to select the detection result by table look-up based on the corresponding relationship between the pre-stored detection result and the gain control strategy.

The target frequency band is the frequency band planned to be concerned, and according to the principle of software radio, the ideal radio monitoring receiving device realizes the digitization of signals by direct radio frequency sampling. However, in practical engineering implementation, because the frequency range of the radio frequency signal is very wide, when the signal reaches a certain frequency range, the existing AD sampling technology cannot meet the sampling rate requirement of direct radio frequency sampling. For example, the maximum sampling rate of the conventional 16-Bit AD sampling chip is 250MB/s, and if the sampling rate of the signal needs to be increased on the basis of the maximum sampling rate, the conventional chip is difficult to further increase, and only the sampling rate is increased by reducing the number of sampling bits of the signal, which results in the reduction of the sampling precision of the signal and the increase of the error of signal measurement.

In order to meet the requirements of sampling precision and the coverage of radio frequency, a superheterodyne receiving mode is generally adopted in engineering, a broadband radio frequency signal is firstly reduced to an intermediate frequency meeting the actual sampling capacity range, and then the signal receiving process of software radio is realized through AD sampling digitization. The selection of the intermediate frequency needs to be comprehensively selected according to the measurement accuracy, the signal bandwidth, the real-time dynamic range, the sensitivity and the like required by signal measurement. When receiving narrow-band communication signals, a lower intermediate frequency (such as 10.7MHz) can be properly selected, the sampling rate required by the intermediate frequency is lower, the sampling bit number can be properly increased, and higher measurement accuracy and real-time dynamic range can be obtained; when receiving broadband signals, a higher intermediate frequency can be properly selected (for example, the signal bandwidth is 10MHz, the intermediate frequency is 21.4MHz, the signal bandwidth is 80MHz, and the intermediate frequency is 70MHz), at this time, the sampling rate required by the intermediate frequency to meet the requirement of signal measurement bandwidth is increased according to the bandwidth range, and at the same time, the sampling rate of the signal is also increased, so that the measurement accuracy and the real-time dynamic range of a part are sacrificed to a certain extent.

B. The broadband intermediate frequency signal is converted into a digital intermediate frequency signal through AD conversion; then, carrying out digital signal processing on the digital intermediate frequency signal to obtain a broadband signal frequency spectrum; and continuously scanning the frequency spectrum of the broadband signal to obtain each sub-signal in the target frequency band. The digital signal processing process comprises the following steps: AD data acquisition, orthogonal transformation, FIR filtering, FFT transformation, window function processing, convolution processing and the like (the same below).

The following operations are respectively executed on the sub signals:

C. and judging whether the corresponding sub-signal is an unconventional signal or not according to the characteristic of the sub-signal, and if so, executing D.

And performing independent signal characteristic measurement on each scanned sub-signal to obtain characteristic parameters of the signal in a time domain, a frequency domain, a modulation domain and a code domain, and rapidly identifying and judging the type of the signal by comparing the characteristic parameters with a standard signal characteristic sample library. Meanwhile, the threat level is determined by comparing with a legal station library. The standard signal characteristic sample library stores characteristic parameters of a plurality of conventional signals in a time domain, a frequency domain, a modulation domain and a code domain, the types of the sub-signals can be determined through comparison, and the more samples are stored in the library, the more accurate the judgment result is. Furthermore, it is necessary to determine whether the sub-signal is legal, that is, whether the sub-signal is sent by a legal station, so that the sub-signal needs to be compared with the legal signal of the legal station stored in the legal station library.

In addition, the neuron can be used for learning various signals obtained by historical scanning, training a discrimination result to obtain a signal classifier, and the neuron can be selected from an existing machine learning model (such as a convolutional neural network). The signal classifier continuously accumulates feature models of various signals. And classifying the scanned sub-signals respectively by using the trained signal classifier, and judging the type of each sub-signal.

The discrimination result of the sub-signal type includes two categories of conventional signals and non-conventional signals. Generally, a general modulation method and a communication method are mostly adopted for a conventional signal, which is easy to identify. However, for an illegal frequency-used signal using an irregular modulation signal, the signal characteristics of the signal are greatly different from those of a conventional signal communication signal because the signal uses a customized method such as a communication method, signal modulation, channel coding and the like, or uses a complicated communication method such as frequency hopping, spread spectrum, frequency hopping and spread spectrum, and the signal belongs to the irregular signal. A conventional signal is a signal that includes recognizable features in terms of time domain, frequency domain, modulation domain, and code domain, whereas an irregular signal is a signal whose features in terms of time domain, frequency domain, modulation domain, and code domain are not recognizable (or cannot be recognized by conventional methods).

D. Aiming at the non-conventional signals, the communication characteristics of the sub-signals are completely imitated to carry out anti-interference release in a signal recording mode, so that the subsequent signals are influenced to be received, and the effect of blocking the communication is achieved. For recording and copying signals, signal data of digital intermediate frequency signals corresponding to the sub-signals within a period of time are collected and intercepted, and then digital-to-analog conversion, filtering, up-conversion and amplification are carried out, so that the effect of simulating various unconventional signals is achieved. Description of filtering: harmonic waves and stray signals generated by the up-conversion and amplification circuit are filtered by the filter circuit, so that the required interference signals are output without interfering other normal signals.

Certainly, for recording and copying signals, data of the sub-signals can be directly intercepted and played back, but huge data volume is needed for storing the sub-signals due to high frequency and high power of the sub-signals, and therefore, after the baseband signals are intercepted, frequency conversion and amplification are carried out, and therefore the difficulty in acquiring and storing the data volume is reduced.

Example two

As shown in fig. 2, the present embodiment discloses a disturbance suppression method, which includes the following steps:

A. and converting the received radio frequency signal into a broadband intermediate frequency signal of a target frequency band. For the collected radio frequency signals, firstly, preselecting and amplifying, wherein the preselecting and amplifying process comprises the steps of performing preselection filtering on frequency bands outside a required frequency range in the radio frequency signals, and selecting the required frequency range for amplification; and mixing the signals subjected to pre-selection amplification, performing down-conversion to obtain intermediate frequency signals of a target frequency band, and performing intermediate frequency filtering on the intermediate frequency signals based on the set target frequency band to filter out signals outside the intermediate frequency band, so that aliasing interference of the signals outside the intermediate frequency band during intermediate frequency acquisition is avoided, and broadband intermediate frequency signals (namely baseband signals) suitable for data acquisition are obtained. The target frequency band is the frequency band of planned interest.

B. The broadband intermediate frequency signal is converted into a digital intermediate frequency signal through AD conversion; then, carrying out digital signal processing on the digital intermediate frequency signal to obtain a broadband signal frequency spectrum; and continuously scanning the frequency spectrum of the broadband signal to obtain each sub-signal in the target frequency band.

The following operations are respectively executed on the sub signals:

C. and judging the type of the branch signal according to the characteristic of the branch signal.

And performing independent signal characteristic measurement on each scanned sub-signal to obtain characteristic parameters of the signal in a time domain, a frequency domain, a modulation domain and a code domain, and rapidly identifying and judging the type of the signal by comparing the characteristic parameters with a standard signal characteristic sample library. Meanwhile, the threat level is determined by comparing with a legal station library. The standard signal characteristic sample library stores characteristic parameters of a plurality of conventional signals in a time domain, a frequency domain, a modulation domain and a code domain, the type of the sub-signal can be determined through comparison, and further, whether the sub-signal is legal or not needs to be judged, namely whether the sub-signal is sent by a legal station or not needs to be judged, so that the sub-signal needs to be compared with the legal signal of the legal station stored in the legal station library.

In addition, the neuron can be used for carrying out deep learning on various signals obtained by historical scanning, and training a discrimination result to obtain a signal classifier, wherein the signal classifier continuously accumulates feature models of various signals. And classifying the scanned sub-signals respectively by using the trained signal classifier, and judging the type of each sub-signal.

The discrimination result of the sub-signal type includes two categories of conventional signals and non-conventional signals. A conventional signal is a signal that includes recognizable features in terms of time domain, frequency domain, modulation domain, and code domain, whereas an irregular signal is a signal whose features in terms of time domain, frequency domain, modulation domain, and code domain are not recognizable (or cannot be recognized by conventional methods).

D. And matching a corresponding interference handling strategy in a preset strategy library based on the type of the binary signal discrimination. The strategy base stores the signal type and the corresponding interference handling strategy in a correlated manner. The interference processing strategy comprises the following steps: no treatment is performed on legitimate signals; alarming is carried out on the unknown signals, and corresponding treatment is carried out after the alarming is determined; the interference blocking can be directly carried out on illegal signals. For the policy repository, the interference handling policies can be created, edited, and deleted as needed. Corresponding to the type of the sub-signal, the corresponding interference handling strategies are also classified into two broad categories, wherein for regular signals, regular interference handling strategies are matched; for non-conventional signals, non-conventional interference handling strategies are matched.

E. And generating a corresponding interference signal according to the matched interference handling strategy. Generally speaking, firstly, according to a matched interference handling strategy, a digital interference signal corresponding to a strategy requirement is generated, and then, after digital-to-analog conversion, a corresponding analog interference signal is obtained. And for the analog interference signal, the analog interference signal is transmitted after filtering, radio frequency up-conversion and amplification.

And (3) corresponding to a conventional interference handling strategy (including strategies corresponding to signals confirmed as illegal in unknown signals and signals directly confirmed as illegal), carrying out suppression on the radio frequency signals by noise interference signals with the same frequency, the same modulation mode and the same modulation degree/code rate. Corresponding to the non-conventional interference handling strategy (including the strategy corresponding to the signal confirmed as illegal in the unknown signal and the signal directly confirmed as illegal), the method completely imitates the signal communication characteristic of the signal recording mode to carry out anti-interference emission and influence the receiving of the subsequent signal, thereby achieving the effect of blocking communication. For recording and copying of signals, signal data of digital intermediate frequency signals corresponding to the sub-signals within a period of time are collected and intercepted, and then digital-to-analog conversion, up-conversion and amplification are carried out to realize playback of the signals, so that the effect of simulating various unconventional signals is achieved.

It should be noted that, the invention combines the receiving of the target radio frequency signal and the generation of the interference signal, effectively enhances the discovery and tracking capability of the target signal, and improves the real-time property of the radio frequency signal generation. On the other hand, the invention implements different interference strategies according to different target signals, generates interference signals consistent with the characteristics of each sub-signal, has strong pertinence, and can realize the targeted suppression of various unconventional radio frequency signals.

EXAMPLE III

Referring to fig. 3, the present embodiment discloses an interference suppressor using signal emulation, which includes a radio frequency receiving unit, a signal processing unit, and a radio frequency transmitting unit.

The radio frequency receiving unit comprises a pre-selection amplifying module, a down-conversion module and an intermediate frequency filtering module.

The pre-selection amplification module performs pre-selection amplification on the acquired radio frequency signals, and the pre-selection amplification processing process includes pre-selection filtering on frequency bands outside a required frequency range in the radio frequency signals and selecting the required frequency range for amplification. The down-conversion module carries out frequency mixing on the signal after preselection amplification, the down-conversion is the intermediate frequency signal of target frequency range, and the intermediate frequency filtering module carries out intermediate frequency filtering on the intermediate frequency signal based on the target frequency range of setting for, and the broadband intermediate frequency signal that is fit for data acquisition is obtained to the out-of-band signal of filtering intermediate frequency, avoids the aliasing interference of the out-of-band signal when the intermediate frequency is gathered.

The signal processing unit comprises an intermediate frequency data acquisition module, an intermediate frequency digital signal processing module, a signal analysis processing module and a gain control module.

The intermediate frequency data acquisition module performs analog-to-digital conversion on the broadband intermediate frequency signal to obtain a digital intermediate frequency signal; the intermediate frequency digital signal processing module performs digital signal processing on the digital intermediate frequency signal to obtain a broadband signal frequency spectrum; the signal analysis processing module scans and discovers the broadband signal frequency spectrum, identifies the characteristics and generates interference signals.

Scanning to find out: and continuously scanning the frequency spectrum of the broadband signal to obtain each sub-signal in the target frequency band.

And (3) feature identification: and for each sub signal, judging whether the corresponding sub signal is an unconventional signal or not according to the characteristics of the sub signal. And performing independent signal characteristic measurement on each scanned sub-signal to obtain characteristic parameters of the signal in a time domain, a frequency domain, a modulation domain and a code domain, and rapidly identifying and judging the type of the signal by comparing the characteristic parameters with a standard signal characteristic sample library. Meanwhile, the threat level is determined by comparing with a legal station library.

Interference signal generation: for the unconventional radio frequency signals, the communication characteristics of the sub-signals are completely imitated in a signal recording mode to carry out anti-interference discharge, and the subsequent signal receiving is influenced, so that the effect of blocking communication is achieved. For recording and copying signals, signal data in a period of time corresponding to the broadband intermediate frequency signals of the sub-signals are collected and intercepted to be used as copying signals, and then digital-to-analog conversion is carried out on the copying signals.

The gain control module respectively detects the signal intensity of the radio-frequency signal collected by the radio-frequency receiving unit and the signal intensity of the output broadband intermediate-frequency signal in real time, and selects a corresponding gain control strategy by looking up a table based on the corresponding relation between the detection result, the preset detection result and the gain control strategy so as to perform gain control on the signal intensity of the collected radio-frequency signal and the signal intensity of the broadband intermediate-frequency signal obtained by processing. The output power of the collected radio frequency signals is ensured to be in a preset range, and the radio frequency signals with different intensities can be accurately received.

The radio frequency up-conversion unit comprises a signal filtering module, an up-conversion module and an amplification module. The signal filtering module filters the imitation signal (after digital-to-analog conversion), and the imitation signal is up-converted by the up-conversion module, amplified by the amplification module and transmitted.

Example four

The embodiment discloses an interference suppressor which can suppress various irregular radio frequency signals. As shown in fig. 3, the interference suppressor includes a radio frequency receiving unit, a signal processing unit, and a radio frequency up-conversion unit.

The intermediate frequency data acquisition module performs analog-to-digital conversion on the broadband intermediate frequency signal to obtain a digital intermediate frequency signal; the intermediate frequency digital signal processing module is used for carrying out digital signal processing on the digital intermediate frequency signal and obtaining a lane broadband signal frequency spectrum; the signal analysis processing module scans and discovers the broadband signal spectrum, identifies the characteristics, matches strategies and generates interference signals.

And (3) feature identification: and for each sub signal, judging the type of the corresponding sub signal according to the characteristics of the sub signal. And performing independent signal characteristic measurement on each scanned sub-signal to obtain characteristic parameters of the signal in a time domain, a frequency domain, a modulation domain and a code domain, and rapidly identifying and judging the type of the signal by comparing the characteristic parameters with a standard signal characteristic sample library. Meanwhile, the threat level is determined by comparing with a legal station library.

Strategy matching: and matching a corresponding interference handling strategy in a preset strategy library corresponding to the discrimination result of the sub-signal type. The strategy base stores the signal type and the corresponding interference handling strategy in a correlated manner. The interference processing strategy comprises the following steps: no treatment is performed on legitimate signals; alarming is carried out on the unknown signals, and corresponding treatment is carried out after the alarming is determined; the interference blocking can be directly carried out on illegal signals. For the policy repository, the interference handling policies can be created, edited, and deleted as needed. Corresponding to the type of the sub-signal, the corresponding interference handling strategies are also classified into two broad categories, wherein for regular signals, regular interference handling strategies are matched; for non-conventional signals, non-conventional interference handling strategies are matched.

Interference signal generation: and generating a corresponding interference signal according to the matched interference handling strategy.

Generally speaking, firstly, according to a matched interference handling strategy, a digital interference signal corresponding to a strategy requirement is generated, and then, after digital-to-analog conversion, a corresponding analog interference signal is obtained. And for the analog interference signal, the analog interference signal is transmitted after radio frequency up-conversion and amplification processing.

And (3) corresponding to a conventional interference handling strategy (including strategies corresponding to signals confirmed as illegal in unknown signals and signals directly confirmed as illegal), carrying out suppression on the radio frequency signals by noise interference signals with the same frequency, the same modulation mode and the same modulation degree/code rate. Corresponding to the non-conventional interference handling strategy (including the strategy corresponding to the signal confirmed as illegal in the unknown signal and the signal directly confirmed as illegal), the method completely imitates the signal communication characteristic of the signal recording mode to carry out anti-interference emission and influence the receiving of the subsequent signal, thereby achieving the effect of blocking communication. For recording and copying signals, signal data within a period of time of digital intermediate frequency signals corresponding to the signals are collected and intercepted, and then digital-to-analog conversion is carried out on the signal data.

The radio frequency up-conversion unit comprises a signal filtering module, an up-conversion module and an amplification module.

The signal filtering module carries out filtering processing on the signal data, the up-conversion module carries out radio frequency up-conversion on the interference signal after filtering processing, and the interference signal is amplified by the amplifying module and then transmitted out through the antenna.

EXAMPLE five

Based on the fourth embodiment, as shown in fig. 4, the fourth embodiment discloses a multi-channel radio frequency signal interference suppressor, wherein a radio frequency signal received by a monitoring antenna is processed by a radio frequency receiving unit 1, and then converted into a broadband analog intermediate frequency signal, and the analog intermediate frequency signal is converted into a digital intermediate frequency signal after being sampled by an ADC of a signal processing unit 2, and then input into an FPGA for digital signal processing, so as to obtain characteristic parameters of a target signal, and store signal data thereof.

The FPGA outputs the acquired target signal information to the ARM or the DSP; and the ARM or the DSP performs interference strategy matching on the target signal information, and selects the most suitable radio frequency signal strategy according to different types of target signals. After the ARM or the DSP identifies and selects the matched interference strategy, the FPAG generates a corresponding radio frequency signal according to the strategy and outputs the generated analog signal through the DAC. The ARM or the DSP also monitors the power of the radio-frequency signals received by the radio-frequency receiving unit 1 and the power of the output broadband analog intermediate-frequency signals, and respectively controls the gain of the radio-frequency signals received by the radio-frequency receiving unit 1 and the power of the output broadband analog intermediate-frequency signals based on the monitoring result by utilizing a pre-stored gain control strategy, so that the power of the broadband analog intermediate-frequency signals received by the ADC of the final signal processing unit 2 is ensured to be in a proper (preset) range, and the system can accurately receive the radio-frequency signals with different strengths.

The signal output by the DAC is conditioned (filtered), frequency-converted and amplified by the radio frequency up-conversion unit 3, and is output to a transmitting antenna for signal transmission.

EXAMPLE six

The embodiment discloses the preselection amplification process of the radio frequency signal in the above embodiment. First, the preselection amplification includes signal preselection and power amplification. Signal preselection is the preselection filtering of signals outside the desired signal band.

At present, the frequency spectrum resource management of China adopts a static mode to distribute the frequency utilization frequency of various frequency utilization equipment, and various services all assign and use frequency spectrum resources according to the related frequency of the state. Such as: the frequency modulation broadcast is in a frequency range of 87-108 MHz; the communication frequency band of the interphone is a 400MHz frequency band; the public mobile communication is a 900MHz (2G) frequency band, a 1.8GHz (4G) frequency band and a 3.5-4 GHz (5G) frequency band; WIFI is a 2.4GHz frequency band and the like.

In order to improve the receiving sensitivity during signal monitoring and measurement and reduce the interference of signals in other frequency bands, signal pre-selection processing needs to be added at the front end of radio frequency receiving, and signals out of band are continuously filtered at the front end of receiving, so that the interference of adjacent channels or signals out of band is reduced. For example: the frequency modulation broadcast frequency range is 87-108 MHz, the civil aviation navigation and communication frequency range is 108-137 MHz, when receiving the signal of the civil aviation frequency range, if the preselection processing is not carried out, the signal of the frequency modulation broadcast frequency range also enters the receiving front end, and carries out frequency mixing and frequency conversion together with the measured signal. Because frequency modulation broadcast signal power is great, civil aviation frequency channel signal power is less, when carrying out radio frequency input signal detection, can reduce signal gain because of avoiding the input signal distortion, leads to the receiving sensitivity of civil aviation signal to reducing relatively. After the preselection filter for frequency modulation broadcasting is added, the receiving interference of radio frequency input front-end broadcasting signals to civil aviation signals can be effectively reduced, and the required signals can be received better.

Power amplification is the power amplification of the desired signal.

The invention is not limited to the foregoing embodiments. The invention extends to any novel feature or any novel combination of features disclosed in this specification and any novel method or process steps or any novel combination of features disclosed.

Claims

1. A method of suppressing disturbances, comprising the steps of:

A. converting the received radio frequency signal into a broadband intermediate frequency signal of a target frequency band; in the process, the signal intensity of the radio-frequency signal collected by the radio-frequency receiving unit and the signal intensity of the output broadband intermediate-frequency signal are detected in real time respectively, and the signal intensity of the collected radio-frequency signal and the signal intensity of the converted broadband intermediate-frequency signal are subjected to gain control based on the corresponding relation between the detection result, the preset detection result and the gain control strategy;

C. judging whether the sub signal is an unconventional signal or not according to the characteristics of the sub signal, if so, executing D, wherein the unconventional signal is a signal with characteristics which cannot be identified; the method for judging whether the branch signal is an unconventional signal or not according to the characteristics of the branch signal comprises the following steps:

or identifying whether the type of the sub-signal is an unconventional signal or not by using a signal classifier based on the characteristic parameters of the sub-signal in the time domain, the frequency domain, the modulation domain and the code domain, wherein the signal classifier is obtained by deeply learning the characteristic parameters of the sub-signal obtained by historical scanning in the time domain, the frequency domain, the modulation domain and the code domain and the corresponding discrimination type;

D. aiming at the non-conventional signals, the communication characteristics of the sub-signals are imitated in a signal recording mode to obtain interference signals, and then the interference signals are released to suppress corresponding radio frequency signals.

2. The interference suppression method of claim 1, wherein the method of emulating the sub-signal communication characteristics in step D comprises:

3. A method of suppressing disturbances, comprising the steps of:

4. The interference suppression method according to claim 3, wherein the step E of imitating the communication characteristics of the sub-signals to obtain the interference signals comprises:

5. The interference suppression method according to claim 3, wherein in the step C, the method for discriminating the type of the partial signal according to the feature of the partial signal includes:

6. An interference suppressor is characterized by comprising a radio frequency receiving unit, a signal processing unit and a radio frequency up-conversion unit;

the signal processing unit comprises an intermediate frequency data acquisition module, an intermediate frequency digital signal processing module, a signal analysis processing module and a gain control module; the intermediate frequency data acquisition module performs analog-to-digital conversion on the broadband intermediate frequency signal to obtain a digital intermediate frequency signal; the intermediate frequency digital signal processing module performs digital signal processing on the digital intermediate frequency signal to obtain a broadband signal frequency spectrum; the signal analysis processing module carries out continuous spectrum scanning on the signal spectrum of the broadband intermediate-frequency signal to obtain each sub-signal in a target frequency band; for each sub signal, judging whether the corresponding sub signal is an unconventional signal or not according to the characteristics of the sub signal, if so, acquiring and intercepting signal data of a digital intermediate frequency signal corresponding to the sub signal in a preset time period as a simulated signal, and performing digital-to-analog conversion on the simulated signal; the gain control module respectively detects the signal intensity of the radio-frequency signal acquired by the radio-frequency receiving unit and the signal intensity of the output broadband intermediate-frequency signal in real time, and performs gain control on the acquired radio-frequency signal and the signal intensity of the broadband intermediate-frequency signal obtained by processing based on the corresponding relation between the detection result, the preset detection result and the gain control strategy;

7. The interference suppressor of claim 6 wherein the method for determining whether a corresponding sub-signal is an irregular signal according to the characteristics of the sub-signal by the signal analysis processing module comprises:

8. An interference suppressor is characterized by comprising a radio frequency receiving unit, a signal processing unit and a radio frequency up-conversion unit;

the signal processing unit comprises an intermediate frequency data acquisition module, an intermediate frequency digital signal processing module, a signal analysis processing module and a gain control module; the intermediate frequency data acquisition module performs analog-to-digital conversion on the broadband intermediate frequency signal to obtain a digital intermediate frequency signal; the intermediate frequency digital signal processing module performs digital signal processing on the digital intermediate frequency signal to obtain a broadband signal frequency spectrum; the signal analysis processing module carries out continuous spectrum scanning on the signal spectrum of the broadband intermediate-frequency signal to obtain each sub-signal in a target frequency band; for each sub signal, judging the type of the corresponding sub signal according to the characteristics of the sub signal, wherein the type of the sub signal comprises a conventional signal and an unconventional signal; matching a corresponding interference handling strategy in a preset strategy library based on the type of the binary signal discrimination; the strategy base stores signal types and corresponding interference handling strategies in a correlated manner; the interference handling policies comprise a conventional interference handling policy corresponding to a conventional signal and an irregular interference handling policy corresponding to an irregular signal; generating a corresponding interference signal according to the matched interference handling strategy; the method for generating the interference signal corresponding to the unconventional interference handling strategy comprises the following steps: simulating the communication characteristics of the sub-signals in a signal recording mode to obtain interference signals; the gain control module respectively detects the signal intensity of the radio-frequency signal acquired by the radio-frequency receiving unit and the signal intensity of the output broadband intermediate-frequency signal in real time, and performs gain control on the acquired radio-frequency signal and the signal intensity of the broadband intermediate-frequency signal obtained by processing based on the corresponding relation between the detection result, the preset detection result and the gain control strategy;

9. The interference suppressor of claim 8 wherein the method for determining the type of the corresponding sub-signal by the signal analysis processing module based on the characteristics of the sub-signal comprises: