WO2014019331A1

WO2014019331A1 - Self-adaptive quick narrowband interference suppression device

Info

Publication number: WO2014019331A1
Application number: PCT/CN2013/000117
Authority: WO
Inventors: 蔺晓龙; 翟昆朋; 何文涛; 金亮良; 李尤; 徐建华; 殷明
Original assignee: 江苏物联网研究发展中心
Priority date: 2012-08-02
Filing date: 2013-02-04
Publication date: 2014-02-06
Also published as: CN102769478A; CN102769478B

Abstract

Disclosed is a self-adaptive quick narrowband interference suppression device. The device comprises one or more DFT modules, an interference suppression module, an interference acquisition control module, and an interference tracking control module. The device completes the steps of: firstly, acquiring a narrowband interference signal, wherein the interference acquisition control module uses a multistage DFT frequency detection algorithm to control the DFT module to subject an input signal to narrowband interference frequency detection; after detecting the narrowband interference, initializing and starting up the interference suppression module to filter a plurality of narrowband interferences; and then tracking the narrowband interference signal by using the interference tracking control module to control the DFT module to subject the detected narrowband interference frequency to detection tracking and updating the coefficient of an IIR wave trap in the interference suppression module, thereby conducting self-adaptive tracking and suppression of the narrowband interference. The present invention can quickly detect a plurality of narrowband interferences and continuously track the interference frequency variation, and has the advantages that the implementation cost is low, the detection is quick, and the self-adaptive tracking of the frequency variation of the narrowband interference can be conducted.

Description

Adaptive fast narrowband interference suppression device

The invention belongs to the field of spread spectrum communication, and in particular relates to an adaptive fast narrowband interference suppression device. Background technique

The Global Navigation Satellite System (GNSS) provides users with positioning and navigation services, and has been widely used in the fields of consumption, transportation, power, and defense. GNSS includes the United States' Global Positioning System (GPS), Russia's Gruss system (GL0NASS), the European Union's Galileo system (Galileo), China's Beidou system (BD) and other enhancement systems.

The signal intensity of the GNSS received by the ground is around -130dBm, far below the noise power. Interference from other communication equipment leaking into the GNSS signal band can severely degrade the performance of the receiver and even render the receiver inoperable. The most common type of interference is the Continuous Wave Interference, which is a narrowband interference.

Current narrowband interference suppression techniques include the following.

Frequency domain based narrowband interference suppression technology. It is necessary to use Fast Fourier Transform (FFT) and its inverse transform (IFFT) to eliminate narrowband interference in the frequency domain. For example, Chinese Patent Application No. 200580013652.8, "Receiver for Narrowband Interference Cancellation", Chinese Patent Application No. 201010610524.4, "Frequency-Frequency Receiver Front-End Domain Filtering Anti-Jamming Device and Its Implementation Method", the disadvantage is due to the use of FFT It requires a lot of computing resources, which is complicated to implement and costly.

Narrowband interference suppression technology for adaptive FIR filters. FIR filter + adaptive algorithm, that is, adaptive FIR filter. For example, the Chinese patent entitled "Blind Adaptive Filtering Device and Its Application for Eliminating Narrowband Interference" with the application number of 201010199697.1 has the disadvantage that the number of filters is larger in order to suppress multiple interferences, and the adaptive algorithm is computationally intensive, and the design is completed. It is fixed afterwards and cannot be automatically configured according to the number of interferences.

A narrowband interference suppression technique that cooperates with the cancellation device. Firstly, the characteristics of the frequency, phase and amplitude of the narrowband interference are detected, and then the interference is filtered out by using a parameter-adjustable filter (notch filter); or the reference local signal is subtracted from the input signal to complete the narrowband interference suppression. For example, the Chinese patent “Application No. 00803299.8” maintains the performance quality of broadband systems with narrowband interference. The disadvantage is that the implementation is complex, costly, and has no adaptive tracking ability to change the frequency of interference.

Summary of the invention

SUMMARY OF THE INVENTION The object of the present invention is to overcome the deficiencies of the prior art and to provide an adaptive fast narrowband interference suppression apparatus for achieving fast interference detection, suppression and adaptive tracking with less resource consumption.

According to the technical solution provided by the present invention, the adaptive fast narrowband interference suppression apparatus includes: one or more digital Fourier transform (DFT) modules, performing digital Fourier transform calculation on the input signal;

Two interference suppression modules suppress the detected narrowband interference, and the interference suppression module includes a multi-stage cascaded IIR trap;

An interference capture control module that controls the DFT module to detect a narrowband interference frequency in the input signal; One or more interference tracking control modules, controlling the DFT module and the interference suppression module to track narrowband interference;

In the capture phase, the input signal is connected to the interference suppression module input, and is output by the interference suppression module; the input signal is also connected to the signal input of the DFT module, the output of the DFT module is connected to the input of the interference capture control module, and the interference capture control module output is connected to the DFT module. Control input and coefficient input of the interference suppression module;

In the tracking phase, the input signal is connected to the interference suppression module input, and is output by the interference suppression module; the input signal is also connected to the signal input of the DFT module, the output of the DFT module is connected to the input of the interference tracking control module, and the interference tracking control module output is connected to the DFT module. The control input and the coefficient input of the interference suppression module, and the coefficient output of the interference suppression module is connected to the input of the interference tracking control module;

The detection and acquisition process of the narrowband interference signal is: the input signal received by the narrowband interference is used as the input of the DFT module, and the interference acquisition control module uses the multi-level DFT frequency detection algorithm to control the DFT module to calculate the frequency spectrum of the input signal using the digital Fourier transform; After completion, the interference capture control module detects the narrowband interference frequency in the frequency spectrum, and converts the frequency information into an interference suppression module in which the IIR notch coefficient is placed in the interference suppression module; the frequency of the narrowband interference of the interference suppression module on the input signal Filtering is performed; the tracking process of the narrowband interference signal that has been detected is: After the detection capture is completed and the interference suppression module is started, the interference tracking control module selects a running IIR trap in the interference suppression module to obtain the IIR. The center frequency and bandwidth of the trap, the central frequency and bandwidth are used as configuration parameters to control the DFT module to perform DFT transform calculation on the input signal; the interference tracking control module determines the maximum amplitude of the calculation result: if it is greater than the threshold, the maximum is based on the amplitude Frequency update of the value The coefficient of the IIR notch; if it is less than the threshold, the interference of the frequency has disappeared, and the IIR trap is turned off.

The interference capture control module uses a multi-stage DFT frequency detection algorithm as follows: assuming that the frequency range to be detected is S, a total of M levels are used for detection; first, level 1 detection, the range of ^f is performed at a frequency interval of /; After the DFT detection, after the result is obtained, the result of the frequency amplitude exceeding the threshold is recorded in the first table Table-1; then the second level detection is started, and the frequency components recorded in the first table Table-1 are sequentially performed at a frequency interval of / ₂ . After the DFT test is performed, after the result is obtained, the result of the frequency range exceeding the threshold is recorded in the second table Table-2; the next level detection is performed by analogy; until the Mth level - the detection is completed, the final resolution is f _M is obtained. DFT test results.

In the multi-level DFT frequency detection algorithm, the total time required to consume is modeled as follows:

Where: /i, / ₂ ,..., /M respectively represent the frequency interval of the first, second, ..., M level detection, ie the frequency resolution, fu represents the final frequency resolution, determined by the design target; Ν indicates the number of frequencies recorded in each level, which is also the number of narrowband interference suppression defined in the design;

First, the initial value Μ0 is obtained for the series, and then the minimum value is obtained for the equation (5), and the frequency interval of each level detection is determined, ..., /^, substituted into the equation (5), and the minimum time of the multi-stage DFT frequency detection time is obtained. Depreciate, then check if the Γ value meets the requirements, if not, increase the value of the Μ ,, repeat the above steps, Until the required detection time Γ and the corresponding number of stages M, the detected frequency interval assumes that the IIR trap operating center frequency is 3 dB bandwidth is ^3^, the interference tracking control module uses the DFT module to the IIR notch Frequency detection is performed in the frequency range of _3<3⁄4 near the center frequency; if the amplitude of the result is greater than the threshold, the narrowband interference still exists, and the coefficient of the IIR trap is updated according to the frequency at which the amplitude is maximum; If the maximum amplitude of the result is less than the threshold, indicating that the narrowband interference of the frequency has disappeared, the IIR trap is turned off; the interference tracking control module can continuously detect the presence or absence of interference and continuously track the frequency variation of the interference.

Using Λ as the frequency resolution, using DFT to detect the frequency range of _3ί/β , its ability to track frequency changes is -

When there is only one DFT module, it is necessary to use time division multiplexing technology, that is, when one DFT module is allocated to multiple IIR traps in turn, its ability to track frequency changes becomes:

Sweep = ^ Hz I s) ( ₈ ) where: ^ is the number of multiplexed IIR notches;

The design target determines the value, firstly determine J and SPT _{3 (3⁄4} value, according to the design goal and use formula (8) to determine the value of Λ; compare Λ and ^ size, check whether it meets ^ ≥ 3 / ο, if not satisfied , you need to reduce V, or increase S _3i3⁄4 , repeat the above steps until you get the required 3dB bandwidth as Sff _3i3⁄4 and the detected frequency resolution Λ.

The IIR trap of the present invention uses a 1st order or a 2nd order structure.

The present invention can use multiple DFT modules to simultaneously track multiple IIR traps in the interference suppression module, or can use a DFT module to track multiple IIR traps in a time division multiplexed sequence.

The results calculated by the DFT module are outputted in order of magnitude values from largest to smallest.

The advantages of the invention are:

1. Calculate the spectrum of the input signal using a digital Fourier transform (DFT) module to reduce hardware computational resource consumption;

2. Design and control the DFT module using a multi-level DFT frequency detection algorithm to greatly reduce the detection time;

3. Use cascaded IIR notch to suppress multiple narrowband interferences and reduce hardware computing resource consumption;

4. Use the interference tracking algorithm to design and control the DFT module and the interference suppression module to achieve adaptive tracking to suppress narrowband interference.

DRAWINGS

Figure 1 is a schematic diagram of a navigation satellite positioning receiver with narrowband interference suppression.

Figure 2 (a) is a structural diagram of the acquisition mode of the adaptive fast narrowband interference suppression device. Figure 2 (b) is a structural diagram of the tracking mode of the adaptive fast narrowband interference suppression device. Figure 3 is a block diagram of the DFT module.

Figure 4 is a block diagram of the interference suppression module.

Figure 5 is a flow chart of interference capture control (multi-level DFT frequency detection).

Figure 6 is a flow chart of interference tracking control.

detailed description

The invention is further described below in conjunction with the drawings and embodiments of the specification.

Figure 1 shows the structure of a navigation satellite positioning receiver 107 with narrowband interference suppression. The satellite 101 and narrowband interfering signals 102 of a global navigation satellite system (such as a GPS system, a GLONASS system, a Galileo system, a Beidou system, or other global navigation satellite system) are received by the receiver antenna 103 and transmitted to the receiver RF 104 for mixing and filtering. The IF digital signal is generated after the operation such as quantization. A receiver that does not have narrowband interference suppression directly transmits the intermediate frequency digital signal to the receiver baseband 106 for processing. When the interference signal 102 is present, this will cause the receiver baseband 106 to fail to process the satellite signal normally, and the positioning navigation function cannot be realized. The adaptive fast narrowband interference suppression apparatus 105 of the present invention performs frequency detection on the intermediate frequency digital signal output from the radio frequency 104, identifies and suppresses a plurality of narrowband interferences, and simultaneously tracks the frequencies of the interferences, thereby continuously adaptively suppressing narrowband interference. Finally, the output signal after the interference suppression is transmitted to the receiver baseband 106 for measurement and calculation, and the positioning and navigation functions are realized. The receiver 107 is made to have the ability to suppress narrowband interference.

As shown in FIG. 2(a) and FIG. 2(b), the adaptive fast narrowband interference suppression apparatus 105 includes: one or more DFT modules 201, an interference suppression module 202, an interference capture control module 203, and a The interference tracking control module 204 has the following modules connected.

The capture phase: the input signal is connected to the interference suppression module 202 input, and is output by the interference suppression module 202; the input signal is also connected to the signal input of the DFT module 201, the output of the DFT module 201 is connected to the input of the interference capture control module 203, and the interference capture control module 203 outputs The control input of the DFT module 201 and the coefficient input of the interference suppression module 202 are connected.

Tracking phase: the input signal is connected to the interference suppression module 202 input, and is output by the interference suppression module 202; the input signal is also connected to the signal input of the DFT module 201, the output of the DFT module 201 is connected to the input of the interference tracking control module 204, and the interference tracking control module 204 outputs The control input of the DFT module 201 and the coefficient input of the interference suppression module 202 are connected, and the coefficient output of the interference suppression module 202 is connected to the input of the interference tracking control module 204.

The detection acquisition process for the narrowband interference signal is as follows: The input signal subjected to narrowband interference is input to the DFT module 201, and the interference capture control module 203 controls the DFT module 201 to perform calculation using DFT (Digital Fourier Transform) using a multi-stage DFT frequency detection algorithm. The frequency spectrum of the input signal. After the calculation is completed, the interference capture control module 203 detects the narrowband interference frequency in the frequency spectrum, and converts the frequency information into the interference suppression module 202 to place the IIR notch coefficient into the interference suppression module 202. The interference suppression module 202 filters out the frequency of narrowband interference in the input signal.

The tracking process for the narrowband interference signal that has been detected is as follows: After the detection capture is completed and the interference suppression module is activated, the interference tracking control module 204 selects an operating IIR trap in the interference suppression module 202 to obtain the IIR trap. The center frequency and bandwidth of the wave, as the center frequency and bandwidth The configuration parameter controls the DFT module 201 to perform a DFT transform calculation on the input signal. The interference tracking control module 204 determines the maximum value of the calculation result: if it is greater than the threshold, the coefficient of the IIR notch is updated according to the frequency of the maximum amplitude; if it is less than the threshold, the interference of the frequency has disappeared, and the IIR trap.

3 is a structural diagram of a DFT module according to an embodiment of the present invention. The DFT module 201 performs a digital Fourier transform (DFT) on the input signal to calculate a plurality of frequency amplitudes, and then outputs the results in amplitude. The configurable parameter input 301 can control the frequency of the local COS, the SIN carrier 303, the integration time length of the accumulator 304, and the number of DFT calculation results 306. The input signal is multiplied by the local carrier 303 via the mixer 302 and sent to the accumulator 304 for accumulation. The amplitude value of the frequency component is obtained using the amplitude equalizer 305 when the integration is completed, and the value is stored in the register set 306. This is repeated until the number of settlement results input by the input control configuration parameter 301 is completed. Finally, the DFT calculation results are arranged as output according to the amplitude from large to small.

The DFT module uses Digital Fourier Transform (DFT) technology, whose expression:

X{ ) = _j x{n)e- ^j<an where: L is the frequency resolution of the accumulated sample point DFT result:

Where: / _s is the sampling frequency and ^ is the cumulative time of the L sampling points.

Assume resolution /. , the time required to detect the frequency range of the band S is:

Taking the GPS signal as an example, the frequency bandwidth to be detected = 2 χ 10 ^ό ίζ, to reach 100 Hz

2 χ ΐθ ⁶

For the frequency resolution, the detection time ^ ¹ : ^^ : ^{2 is required} . . Traditional DFT detection time is very long.

4 is a structural diagram of an interference suppression module according to an embodiment of the present invention. The interference suppression module 202 implements a narrowband interference suppression function by a plurality of cascaded IIR traps 401. Where -al, bl, -a2, b2 are all configurable coefficients of the IIR notch 401. By inputting the appropriate coefficients, the IIR notch 401 can filter out a specified frequency. Thus, by cascading the IIR filter 401, filtering of a plurality of specified frequencies can be achieved.

Each stage of the IIR trap can use a 1st or 2nd order structure. The most common second-order IIR notch is used to illustrate its working principle. The second-order IIR notch system transfer function:

1 - az~ - a ₂ z

, - 2 cos(iy), 1 - 2 (4 ) 1 z - z

1 - 2k cos( )z - kz Where: ^ is the frequency at which the interference is located; k ≤ l, which is a parameter related to the bandwidth of the filter. The closer the value is to 1, the narrower the bandwidth of the notch, and the wider the bandwidth.

The interference capture control module uses a multi-level DFT frequency detection algorithm that significantly reduces detection time compared to traditional DFT detection algorithms. The principle is as follows: When each level is detected, only a small part of the narrowband interference frequency component will have a larger amplitude than the threshold, so it is recorded and continues to be detected by the next stage. Most of the frequency range in which no narrowband interference exists is Excluded, reducing overall inspection time.

First, we need to design specific parameters of the multi-level DFT frequency detection algorithm. These parameters include: the number of stages M, the range of detection frequencies per level /;, / ₂ , / ₃ ..., the overall detection time Γ.

Assuming the frequency range of the Μ level detection is used, the total time required to spend is modeled as follows:

among them:

/i , / ₂ ,..., /M indicates the frequency interval (frequency resolution) of the 1, 2, ..., M level detection.

Fu represents the final frequency resolution and is determined by the design goals.

N represents the number of frequencies recorded for each level, and is also the narrowband interference suppression defined in the design.

, H-number.

First, take the initial value M0 for the series M, and then find the minimum value for the equation (5), determine the frequency interval /;, / ₂ ,..., ^, for each level of detection, and substitute the expression (5) to obtain multiple levels. DFT frequency detection time minimum time 7\ Then check whether the threshold value meets the requirements. If it is not satisfied, increase the value of the level M. Repeat the above steps until the required detection time Γ and the corresponding number of stages M and the frequency of detection are obtained. interval

/ /*2 "··, /Λ/.

Similarly, taking the GPS signal as an example, the frequency bandwidth to be detected = 2 χ 10 ⁶ Ηζ. To achieve a frequency resolution of 100 Hz, a multi-stage 'DFT frequency detection algorithm is used, assuming that the number of stages is M = 2 and the number of anti-interferences is N = 8, /, = 1710Hz, f ₂ = l00Hz, detection time is:

T = ^2 + 8 * ΛΛ2 = 2.05* (6)

100 ^;

Compared with the traditional frequency detection: the final frequency resolution is 100Hz, but the detection time is only 1% of the traditional detection time (200s), which greatly shortens the detection time.

After determining the parameters of the multi-level DFT frequency detection algorithm, the specific implementation manner is as follows: Assuming that the frequency range to be detected is, a total of M levels are used for detection. First, the first level detection, DFT detection of the range of S by the frequency interval (frequency resolution), after the result is obtained, the result of the frequency amplitude exceeding the threshold is recorded in the first table Table_l; then the second level detection is started, The frequency interval of / ₂ is sequentially subjected to DFT detection for the frequency components recorded in Table-1, and after the result is obtained, in the second table Table_2, the frequency amplitude exceeds the threshold result; then the third level detection, method and method Level 2 detection is similar. And so on, until the M-level detection is completed, the final DFT with resolution is obtained. Taking the 2-level DFT frequency detection algorithm as an example, the control flow is as follows:

First step 501: Perform level 1 detection. The detection frequency range and the detection frequency resolution are /;, and the DFT module 201 is controlled to operate. After the calculation is completed, the output result 306 of the DFT module 201 is judged: the result whose amplitude is greater than the threshold is recorded in the first table Table-1, which is discarded less than the threshold result.

Step 502: Perform a level 2 detection. For the first-level detection, the frequency components in the first table Table-1 are sequentially used for level 2 detection: detection frequency range /;, detection frequency resolution / ₂ , and control DFT module 201 to operate. After the calculation is completed, the output result 306 of the DFT module 201 is judged: the result whose amplitude is greater than the threshold ΊΉ ₂ is recorded in the second table Table_2, and the result smaller than the threshold ί ί ₂ is discarded.

Step 503: Determine whether the result of the first 3⁄4 Table-1 has completed the second level detection, if not, return to the second step 502, and perform the second level detection on the result of not performing the second level detection; otherwise, the description Level 2 testing has been completed and the fourth step continues.

Step 4: 504: Process the results of the second-level frequency detection, including signal processing operations such as fitting, culling, filtering, etc., to make the result more accurate.

Step 505: Convert the detected frequency result into coefficient values -al, bl, -a2, and b2 accepted by the IIR trap in the interference suppression module 202, and sequentially put them into the interference suppression module 202, so that the detected Multiple narrowband interference frequencies are suppressed and the capture control flow is completed.

Figure 6 is a flow chart of interference tracking control.

First, you need to design the parameters of the adaptive tracking algorithm, including: The 3dB bandwidth of the filter is S _3DS ,

Frequency resolution of the DFT detection / o.

Assume that the trap center frequency is ", its 3dB bandwidth is ^^ _β , with Λ as the frequency resolution, using DFT to detect the frequency range of ^ _3ίίΰ , its ability to track the frequency change is - Sweep = (Hz/i

Sweep = ^{Hz I s) ( ₈ ) where: V is the number of multiplexed IIR notches.

Design target decision values, first determine the W and _3T3⁄4 values, and determine the tracking parameters based on the design goals and using equation (8). . Compare Λ with 3 3 _3⁄4 size, check if BW _3dB ≥ 3/ ₀ is satisfied, if not, then reduce V, or increase, repeat the above steps until the required 3dB bandwidth is S _3£3⁄4 and detected. Frequency resolution /. .

After the interference tracking parameters are determined, the specific implementation is as follows: The interference tracking control module uses DFT The module performs frequency detection on the frequency range of _3rf near the center frequency w where the IIR trap is located. If the maximum amplitude of the result is greater than the threshold, it indicates that the narrowband interference still exists, and the coefficient of the IIR notch is updated according to the frequency at which the maximum value is located; if the maximum amplitude of the result is less than the threshold, the narrowband interference of the frequency has disappeared. Turn off the IIR trap. The interference tracking control module can continuously detect the presence or absence of interference and continuously track the frequency change of the interference.

The specific tracking control process is as follows:

The first step 601: Check the interference suppression module 202, and select a running IIR trap 401 to perform the 艮艮。.

Step 602: Using parameters: detecting frequency range ₃ (bandwidth of IIR trap 401), detecting frequency resolution Λ, turning on DFT module 201 to perform DFT frequency detection on IIR trap 401.

The third step 603: processing the result of the interference detection. These processes include signal processing operations such as fitting, culling, filtering, etc., to make the results more accurate.

Step 604: Determine the result: If the maximum amplitude of the DFT detection result is greater than the threshold, the interference still exists, and operation 605 is performed to update the IIR notch coefficient; otherwise, the interference of the frequency has disappeared, and the operation is performed. 606 - Turn off the IIR trap 401.

Claims

1. Adaptive fast narrowband interference suppression device, characterized by: including:

One or more DFT modules (201) perform digital Fourier transform calculations on the input signal; an interference suppression module (202) suppresses the detected narrowband interference, and the interference suppression module (202) includes a multi-stage cascaded IIR trap. wave device(401);

An interference capture control module (203) controls the DFT module (201) to detect the narrow-band interference frequency in the input signal;

One or more interference tracking control modules (204) control the DFT module (201) and the interference suppression module (202) to track narrowband interference;

In the capture phase, the input signal is connected to the input of the interference suppression module (202) and output by the interference suppression module (202); the input signal is also connected to the signal input of the DFT module (201), and the output of the DFT module (201) is connected to the interference capture control The input of the module (203), the output of the interference capture control module (203) is connected to the control input of the DFT module (201) and the coefficient input of the interference suppression module (202);

In the tracking phase, the input signal is connected to the input of the interference suppression module (202) and output by the interference suppression module (202); the input signal is also connected to the signal input of the DFT module (201), and the output of the DFT module (201) is connected to the interference tracking control The input of the module (204), the output of the interference tracking control module (204) is connected to the control input of the DFT module (201) and the coefficient input of the interference suppression module (202), and the coefficient output of the interference suppression module (202) is connected to the interference tracking control module (202). 204) input;

The detection and capture process of narrowband interference signals is: the input signal subject to narrowband interference is used as the input of the DFT module (201), and the interference capture control module (203) uses a multi-level DFT frequency detection algorithm to control the DFT module (201) using digital Fourier Transform and calculate the frequency spectrum of the input signal; after the calculation is completed, the interference capture control module (203) detects the narrow-band interference frequency in the frequency spectrum, and converts the frequency information into the IIR notch (401) coefficient in the interference suppression module (202) Placed in the interference suppression module (202); The interference suppression module (202) filters out the frequency of narrowband interference in the input signal;

The tracking process of the narrowband interference signal that has been detected and captured is: After completing the detection and capture and starting the interference suppression module, the interference tracking control module (204) selects an operating IIR trap (401) in the interference suppression module (202) ), obtain the center frequency and bandwidth of the IIR trap (401), and use the center frequency and bandwidth as configuration parameters to control the DFT module (201) to perform DFT transformation calculations on the input signal; the interference tracking control module (204) judges the calculation results The maximum amplitude of 401).

2. The adaptive fast narrowband interference suppression device according to claim 1, characterized in that the interference capture control module (203) uses a multi-level DFT frequency detection algorithm as follows: assuming that the frequency range to be detected is ^^, a total of M levels are tested; first, the first level is tested, and the range of S is tested by DFT at a frequency interval of Level detection, perform DFT detection on the frequency components recorded in the first table Table-1 in sequence at a / ₂ frequency interval. After obtaining the results, record the frequency in the second table Table_2 The amplitude exceeds the threshold; and so on for the next level of detection; until the M-th level detection is completed, the final DFT detection result with a resolution of f _M is obtained.

3. The adaptive fast narrowband interference suppression device according to claim 2, characterized in that, in the multi-level DFT frequency detection algorithm, the total time required is modeled as follows -

Among them: /1,/2,...,/Α respectively represent the frequency intervals of the 1st, _2nd ,..., M level detection, that is, the frequency resolution,

/M represents the final frequency resolution, which is determined by the design goal; represents the number of frequencies recorded at each level, which is also the number of narrowband interference suppression limited in the design;

First, take the initial value M0 for the series M, and then find the minimum value of equation (5) to determine the frequency interval of each level of detection, ,..., ^. Substitute into equation (5) to get the minimum time of multi-level DFT frequency detection time Γ value, and then check whether the Γ value meets the requirements. If not, increase the value of the series M, and repeat the above steps until the detection time Γ that meets the requirements, the corresponding series M, and the detection frequency interval i, fi are obtained. ,""f i °

4. The adaptive fast narrowband interference suppression device according to claim 1, characterized in that, assuming that the IIR trap (401) has a working center frequency of ^ and its 3dB bandwidth is _3ί/β , the interference tracking control module (204 ) Use the DFT module (201) to perform frequency detection in the frequency range S _3rf near the center frequency of the IIR trap (401); if the maximum amplitude of the result is greater than the threshold, it means that narrowband interference still exists, according to the maximum amplitude Update the coefficient of the IIR notch filter (401) at the frequency where the value is located; if the maximum amplitude of the result is less than the threshold, it means that the narrowband interference at this frequency has disappeared, and the IIR notch filter (401) is turned off; the interference tracking control module (204 ) can continuously detect the presence or absence of interference and continuously track the frequency changes of interference.

5. The adaptive fast narrowband interference suppression device according to claim 4, characterized in that, taking Λ as the frequency resolution, using DFT to detect a frequency range of _3ί¾ , its ability to track frequency changes is -

Sweep = ₍₇₎

When there is only one DFT module (201) and time division multiplexing technology needs to be used, that is, when one DFT module (201) is assigned to multiple IIR notches (401) in turn, its ability to track frequency changes becomes -

Sweep = ^ (Hz / s) ( ₈ ) where: is the number of multiplexed IIR traps (401);

The design goal determines the ^ eep value. First, initially determine the N and β _3ί¾ values, and determine / according to the design goal and the use of formula (8). The value of ; compares /. With the size of ^^ ^, check whether it satisfies _3ί¾ ≥ 3/. , if not satisfied, you need to reduce V, or increase BW _3dB , repeat the above steps until satisfied The required 3dB bandwidth is ₃ and the detection frequency resolution Λ.

6. The adaptive fast narrowband interference suppression device according to claim 1, characterized in that the IIR trap (401) uses a 1st-order or 2nd-order structure.

7. The adaptive fast narrowband interference suppression device according to claim 1, characterized by using multiple DFT modules (201) to simultaneously track multiple IIR traps (401) in the interference suppression module (202), or using A DFT module (201) time-division multiplexes sequential tracking of multiple IIR notches (401).

8. The adaptive fast narrowband interference suppression device according to claim 1, characterized in that the results calculated by the DFT module (201) are arranged and output in order of amplitude values from large to small.