CN106842148A - Linear FM radar based on FRFT disturbs quick suppressing method - Google Patents
Linear FM radar based on FRFT disturbs quick suppressing method Download PDFInfo
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
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Abstract
Quick suppressing method is disturbed the invention discloses a kind of linear FM radar based on FRFT, its main thought is：Radar echo signal is obtained, and interference signal is extracted in the radar echo signal, the interference signal after computation delay treatmentIt is rightCarry out FFT, obtain by the interference signal of Fast Fourier Transform (FFT), and obtain W FRFT exponent number value after calculating the chirp rate rough estimate and required order rough estimate when carrying out FRFT of interference signal of interference signal successively, the two dimensional surface of interference signal is obtained according to W FRFT exponent numbers value correspondence, and then the three-dimensional search figure of interference signal is obtained, and determine the accurate order p of the three-dimensional search figure of interference signal0, then it is calculated p0Interference signal suppression treatment is carried out after radar echo signal after rank FRFT conversion, the radar echo signal X' after interference signal suppresses is obtainedp0(u)；To X'p0U () carries out FRFT inverse transformations, obtain the radar echo signal after FRFT inverse transformations.
Description
Technical field
The invention belongs to Radar Signal Processing Technology field, more particularly to a kind of linear FM radar interference based on FRFT
Quick suppressing method, i.e., the linear FM radar based on Fourier Transform of Fractional Order (FRFT) disturbs quick suppressing method, is applicable
The radar chaff of linear FM signal suppresses in frequency domain.
Background technology
Radar is target information acquisition, commander's control, precise guidance and Strike in Information Battlefield and armament systems
Most important equipment in combat system-of-systems, destroys the normal work of radar, can not only destroy the important information source of combat system-of-systems,
Also the overall fighting efficiency of combat system-of-systems can be had a strong impact on.
Radar electronic warfare is enemy radar to be carried out investigations, is disturbed, destroyed, and protection enemy detects to our radar
The ECM looked into, disturb and destroy, radar electronic warfare mainly including radar investigate, radar chaff and destroy, radar protection,
The purpose of radar electronic warfare be by carrying out to enemy radar investigation, interference and destroy, obtain enemy weapon equipment, deployment of forces,
The valuable information of the aspects such as operational commanding；In important fight and course of operation, the armament systems of enemy are made to fail, command control
Failure processed, equipment loss, for eliminate enemy, preserve oneself, obtain war victory create conditions.
With the development of electronic warfare, be faced with the interference being in various forms in radar communication, such as AM interference, frequency modulation interference,
Vertically hung scroll-frequency modulation composite interference and Deceiving interference, linear frequency modulation (LFM) are deposited respectively between interference signal and useful signal and noise
Coupled in stronger time-frequency, classical filtering method is difficult to signal with efficiently separating for disturbing；With video analysis method
And application study deepens continuously, many LFM interference suppression algorithms based on time frequency analysis are occurred in that.At present, for linear tune
Frequently the disturbance restraining method of (LFM) interference signal has three kinds, the interference reconstruct predominantly based on Wigner-Ville distribution (WVD)
Method, the common time domain estimated based on phase and amplitude offset method and based on FRFT frequency domain cancellation suppressing methods, three kinds of suppressions
Method processed all rely on Wigner-Ville distribution (WVD) calculating, WVD is bilinear transformation, and amount of calculation is larger, and sample rate compared with
Height, is unfavorable for Project Realization；In addition, offseting dry make an uproar ratio of the method for interference based on the common time domain that phase and amplitude is estimated
With requirement higher, it is adaptable to strong jamming situation；Though based on FRFT frequency domain cancellation suppressing methods using linear FM signal
Fourier Transform of Fractional Order FRFT special natures carry out AF panel, and with preferable effect, but the method is in parameter Estimation
During, with variable step-size search, amount of calculation is larger.
The content of the invention
For the deficiency that above-mentioned prior art is present, it is an object of the invention to propose a kind of linear frequency modulation based on FRFT
The quick suppressing method of radar chaff, the linear FM radar that this kind is based on FRFT disturbs quick suppressing method, in parameter Estimation
During use simple algorithm, can reduce chirp waveform signal suppression operand.
Basic ideas of the invention are：Interference signal is received first from the antenna of radar, and according to the property of interference signal
Matter, carries out the rough estimate of chirp rate, then carries out precise search, is become based on FRFT so as to calculate correspondence interference signal
Required exponent number is changed, the FRFT conversion of the exponent number is then carried out to interference signal, and carry out spike and hidden every so as to realize doing
Disturb the suppression treatment of signal.
To reach above-mentioned technical purpose, the present invention is adopted the following technical scheme that and is achieved.
A kind of linear FM radar based on FRFT disturbs quick suppressing method, comprises the following steps：
Step 1, obtains radar echo signal, and extract interference signal in the radar echo signal；
Step 2, carries out delay process and conjugation treatment, then by the radar after delay process to radar echo signal respectively
Echo-signal is multiplied with the radar echo signal after conjugation treatment, obtains the interference signal after delay process；
Step 3, Fast Fourier Transform (FFT) FFT is carried out to the interference signal after delay process, is obtained by fast Fourier
The interference signal of conversion, and be calculated the chirp rate rough estimate of interference signal and interference signal successively and carry out FRFT conversion
The order rough estimate of Shi Suoxu；
Step 4, order rough estimate required when FRFT is converted is carried out according to interference signal, obtains W FRFT exponent number value,
The two dimensional surface of interference signal is obtained according to W FRFT exponent numbers value correspondence, and then obtains the three-dimensional search figure of interference signal
Shape, and determine the accurate order p of the three-dimensional search figure of interference signal0；W is the positive integer more than 0；
Step 5, using the accurate order p of the three-dimensional search figure of interference signal0P is carried out to radar echo signal0Rank FRFT
Conversion, obtains p0Radar echo signal after rank FRFT conversion；
Step 6, to p0Radar echo signal after rank FRFT conversion carries out interference signal suppression treatment, obtains interference signal
Radar echo signal after suppression；
Step 7, the radar echo signal after suppressing to interference signal carries out FRFT inverse transformations, after obtaining FRFT inverse transformations
Radar echo signal, the time domain radar return after the radar echo signal after the FRFT inverse transformations suppresses for interference signal is believed
Number.
The present invention has the following advantages that compared with prior art：
First, Fourier Transform of Fractional Order (FRFT) has fully been used in the cancellation process of Linear Frequency Modulation signal of the present invention
And the FRFT of the specific exponent number of linear FM signal is utilized for the property of impulse function so that the present invention is disturbed linear FM signal
Suppression it is more thorough, the performance for finally offseting Radar jam signal is significantly improved.
Second, the calculating of Fourier Transform of Fractional Order (FRFT) of the present invention can be by Fast Fourier Transform (FFT)
FFT is realized so that amount of calculation is greatly reduced, and the presence because of FRFT for linear FM signal focus characteristics so that this hair
It is bright can overcome common time domain offset algorithm for it is larger it is dry make an uproar than the limitation of applicable elements, also have for weak Radar jam signal
Preferable inhibition, increases the scope of application.
3rd, the present invention can make full use of linear during to Fourier Transform of Fractional Order (FRFT) Order- reduction
The property of FM signal, directly obtains the rough estimate result of exponent number, compared with traditional variable step size method, considerably reduces meter
Calculate complexity.
Brief description of the drawings
The present invention is described in further detail with reference to the accompanying drawings and detailed description.
Fig. 1 is that a kind of linear FM radar based on FRFT of the invention disturbs quick suppressing method to realize flow chart；
Fig. 2 is to carry out the result schematic diagram that precise search is obtained using FRFT；
Fig. 3 a front and rear pulse pressure comparison diagrams for interference signal is offseted；
Fig. 3 b front and rear pulse pressure partial enlargement comparison diagrams for interference signal is offseted.
Specific embodiment
Reference picture 1, is that a kind of linear FM radar based on FRFT of the invention disturbs quick suppressing method to realize flow
Figure；The linear FM radar based on FRFT disturbs quick suppressing method, comprises the following steps：
Step 1, radar echo signal is received from the antenna of radar, and radar return is obtained according to the radar echo signal
The relationship between frequency and time distribution map of signal；In the relationship between frequency and time distribution map of radar echo signal, axis of abscissas is time, axis of ordinates
It is frequency；Interference signal is extracted in the relationship between frequency and time distribution map of radar echo signal, the time-frequency distributions of the interference signal are in thunder
It is straight line up in the relationship between frequency and time distribution map of echo-signal, and the interference signal is linear FM signal；Wherein it is determined that
N-th interference signal of sample point is x (n),f0It is the carrier frequency of radar echo signal, fs
It is the sample frequency of radar echo signal, K is the chirp rate of interference signal, and K=B/T, B are the bandwidth of interference signal, and T is dry
The time width of signal is disturbed, n represents n-th sampled point in interference signal, n ∈ [0, NJ- 1], NJ=T × fs, NJIt is adopting for interference signal
Number of samples.
Step 2, carries out delay process and conjugation treatment, then by the radar after delay process to radar echo signal respectively
Echo-signal is multiplied with the radar echo signal after conjugation treatment, obtains the interference signal after delay process
Specifically, the interference signal after the delay processIts expression formula is：
Wherein, M is that the time delay points that delay process includes are carried out to radar echo signal, M<N,E is represented and referred to
Number function, fsIt is the sample frequency of radar echo signal, K is the chirp rate of interference signal, f0It is the load of radar echo signal
Frequently, n represents n-th sampled point in interference signal, n ∈ [0, NJ- 1], NJ=T × fs, NJIt is the sampling number of interference signal.
Step 3, to the interference signal after delay processFast Fourier Transform (FFT) FFT is carried out, is obtained by fast Fourier
The interference signal of conversionAnd be calculated the chirp rate rough estimate u' and interference signal of interference signal successively and carry out FRFT
Order rough estimate p required during conversion.
Specifically, to the interference signal after delay processFast Fourier Transform (FFT) FFT is carried out, is obtained by quick Fu
The interference signal of leaf transformationObtain by the interference signal of Fast Fourier Transform (FFT)Peak point position, and then be calculated
The chirp rate of interference signal accurately estimates a,F is by the interference signal of Fast Fourier Transform (FFT)Middle peak value
The corresponding frequency of point, fsIt is the sample frequency of radar echo signal, M is prolonging of carrying out that delay process includes to radar echo signal
When count.
It is then determined that the FRFT conversion orders p of interference signal；When the FRFT of interference signal is transformed to impulse function, calculate
The chirp rate rough estimate u' of interference signal is obtained,Then the chirp rate according to interference signal is estimated roughly
Meter u', being calculated interference signal carries out order rough estimate p required when FRFT is converted,
Arccot is operated for arc tangent.
Step 4, order rough estimate p required when FRFT is converted is carried out according to interference signal, determines that interference signal is carried out
The excursion [p- △, p+ △] of required order, 0 when accurate FRFT is converted<△<1；△=0.1 in the present embodiment.
The excursion [p- △, p+ △] that required order when accurate FRFT is converted is carried out to interference signal is carried out with step-length δ
It is evenly dividing, δ=0.001；And then W FRFT exponent number value is obtained, interference signal is obtained according to W FRFT exponent numbers value correspondence
(u, h) two dimensional surface, u for radar echo signal carry out p ranks FRFT conversion after corresponding quefrency domain, be abbreviated as u domains；H is u
The corresponding range value in domain；Wherein, w-th the w' two dimensional surface (u of the FRFT exponent numbers value correspondence interference signalw',hw'),
uw'For radar echo signal carries out corresponding the w' quefrency domain after p ranks FRFT is converted, the w' u is abbreviated asw'Domain；hw'For
The w' uw'The corresponding range value in domain, { 1,2 ..., W'}, W are the total number of FRFT exponent number values, W' for w ∈ { 1,2 ..., W }, w' ∈
It is the two dimensional surface total number of interference signal；The total number of FRFT exponent number values it is equal with the two dimensional surface total number of interference signal and
Correspond；W is the positive integer more than 0.
Then p ranks FRFT is carried out to radar echo signal respectively using W FRFT exponent numbers value to convert, respectively obtains W warp
Cross p ranks FRFT conversion two dimensional surfaces；The W is converted by p ranks FRFT two dimensional surface again as one cut into slices into
Row superposition, and then the three-dimensional search figure (p, u, h) of interference signal is obtained, and determine the essence of the three-dimensional search figure of interference signal
True order is p0, p0Represent the corresponding FRFT conversion rank of the corresponding Amplitude maxima point in u domains in the three-dimensional search figure of interference signal
It is secondary, order rough estimate of the p for needed for interference signal is carried out when FRFT is converted.
Step 5, is converted using the corresponding FRFT of the corresponding Amplitude maxima point in u domains in the three-dimensional search figure of interference signal
Order and FRFT have the property of concentration to linear FM signal, and p is carried out to radar echo signal0Rank FRFT is converted, and is obtained
To p0Radar echo signal X after rank FRFT conversionp0U (), its expression formula is：
Xp0(u)=Sp0(u)+Jp0(u)+Np0(u)
Wherein, u for radar echo signal carry out p ranks FRFT conversion after corresponding quefrency domain, be abbreviated as u domains；Sp0U () is
Radar echo signal carries out the useful echo signal included after p ranks FRFT conversion, Np0U () carries out p ranks for radar echo signal
The noise included after FRFT conversion, Jp0U () carries out the interference signal that includes after p ranks FRFT conversion for radar echo signal；If thunder
Up to the interference signal J that echo-signal included after p ranks FRFT conversionp0U () is finite digital signal, then radar echo signal is carried out
The interference signal J included after p ranks FRFT conversionp0U 90% energy above of () is concentrated in u domains with u0Centered on 10Hz arrowbands
It is interior；Radar echo signal carries out the useful echo signal S included after p ranks FRFT conversionp0U () and radar echo signal carry out p ranks
The noise N included after FRFT conversionp0U () is general in u0Place is all without showing aggregation properties, u0For radar echo signal carries out p
Corresponding quefrency domain centre frequency after rank FRFT conversion.
Step 6, to p0Radar echo signal X after rank FRFT conversionp0U () carries out spike and hides every treatment in FRFT domains, i.e.,
Interference signal suppression is processed, and obtains the radar echo signal X' after interference signal suppressesp0(u)。
Specifically, using p0Radar echo signal X after rank FRFT conversionp0U the characteristic of (), chooses suitable threshold value to p0
Radar echo signal X after rank FRFT conversionp0U () carries out spike and hides every wherein suitable threshold value is the dry letter more than 2dB in domain
Than jamming-to-signal ratio is the ratio of interference signal and radar echo signal；So as to curb interference signal in FRFT domains, interference letter is obtained
Number suppress after radar echo signal X'p0U (), its expression formula is：
X'p0(u)=Xp0(u) M (u)=Sp0(u)M(u)+Jp0(u)M(u)+Np0(u)M(u)。
Wherein, frequency is u centered on M (u)0, the preferable bandstop filter with a width of 10Hz, u0For radar echo signal enters
Row p ranks FRFT conversion after corresponding quefrency domain centre frequency, u for radar echo signal carry out p ranks FRFT conversion after it is corresponding
Quefrency domain, is abbreviated as u domains；If it is u that M (u) is centre frequency0, the preferable bandstop filter with a width of 10Hz, then what is obtained is dry
Disturb the radar echo signal X' after signal suppressesp0U () can curb interference signal.
Step 7, the radar echo signal X' after suppressing to interference signalp0U () carries out FRFT inverse transformations, obtain FRFT inversions
Radar echo signal after changing, the time domain radar after the radar echo signal after the FRFT inverse transformations suppresses for interference signal is returned
Ripple signal.
Specifically, the interference signal for being obtained using step 6 suppress after radar echo signal X'p0U () carries out FRFT inversions
Change, so as to the radar echo signal X' after interference signal is suppressedp0U () is transformed into time domain from FRFT domains, complete interference signal
Suppression is processed, and obtains the time domain radar echo signal after interference signal suppresses.
Checking explanation is carried out to effect of the present invention by following computer simulation experiment.
(1) simulated conditions：
Software environment：MATLAB R2011b
Hardware environment：CPU:Inter Pentium G630 2.70GHz
Internal memory:4GB
(2) emulation content：
Assuming that radar emission signal is M sequence, sample frequency Fs=400Hz/s, signal to noise ratio snr=5dB, each sequence code
Shi Kuanwei 20/Fs；Radar echo signal is disturbed by linear FM signal, and its is dry to make an uproar than JNR=15dB, wherein interference letter
Number time width T=8s, bandwidth B=200Hz；In this emulation experiment, the echo of radar emission signal is submerged in interference signal,
And the bandwidth of interference signal is about 1.5 times of transmitted signal bandwidth, and it is covered in the transmission signal of radar, with this hair
Bright method carries out AF panel to the radar echo signal.
Emulation content 1：AF panel is carried out to the radar echo signal with the inventive method.
Emulation content 2：AF panel is carried out to the radar echo signal with conventional method.
Traditional method uses the method for variable step to calculate the optimal factor of FRFT conversion, i.e., first coarse search determines
FRFT converts the approximate range of exponent number, then determines the optimal factor value that FRFT is converted, wherein coarse search and essence by essence search
Searching method respectively with the inventive method the step of it is 4 identical, only the step-length of coarse search is larger, i.e., the step-length of coarse search is 2/
L, L>20, L=100 is selected in this emulation experiment；Given step-length δ is identical for the step of essence search is with the inventive method 4.
(3) simulated effect analysis：
The complexity of the inventive method and conventional method is analyzed first, because difference of the inventive method from conventional method
The rough estimate aspect of FRFT orders is concentrated mainly on, therefore only considers the complexity of FRFT order rough estimates, and assume that radar is returned
The points of ripple signal are N, and then the radar echo signal carries out the coarse search that step-length is L；The inventive method and conventional method
Computation complexity contrast is as shown in table 1, and the inventive method is as shown in table 2 with the run time contrast of conventional method.
Table 1
| Method | The inventive method | Conventional method |
| Time (S) | 55.78 | 64.23 |
Table 2
From table 1 it follows that in the case of jamming performance identical is suppressed, the inventive method complexity is
Compare with conventional method, computation complexity is substantially reduced.
Two kinds of algorithms of being sampled simultaneously under same environment as can be seen from Table 2 are processed, and have larger in run time
Gap, supports the inventive method well.
Interference signal is can be seen that by Fig. 3 a and Fig. 3 b to be curbed well, be 15dB, noise in dry making an uproar than JNR
In the case of for 5dB, after carrying out AF panel to radar echo signal, the pulse pressure signal to noise ratio of useful echo signal is left in 15dB
The right side, can be detected well, reach the requirement of AF panel.
In sum, emulation experiment demonstrates correctness of the invention, validity and reliability.
Obviously, those skilled in the art can carry out various changes and modification without deviating from essence of the invention to the present invention
God and scope；So, if these modifications of the invention and modification belong to the scope of the claims in the present invention and its equivalent technologies
Within, then the present invention is also intended to comprising these changes and modification.
Claims (7)
1. a kind of linear FM radar based on FRFT disturbs quick suppressing method, it is characterised in that comprise the following steps：
Step 1, obtains radar echo signal, and extract interference signal in the radar echo signal；
Step 2, carries out delay process and conjugation treatment, then by the radar return after delay process to radar echo signal respectively
Signal is multiplied with the radar echo signal after conjugation treatment, obtains the interference signal after delay process；
Step 3, Fast Fourier Transform (FFT) FFT is carried out to the interference signal after delay process, is obtained by Fast Fourier Transform (FFT)
Interference signal, and be calculated the chirp rate rough estimate of interference signal successively and interference signal carries out FRFT conversion when institute
The order rough estimate for needing；
Step 4, order rough estimate required when FRFT is converted is carried out according to interference signal, obtains W FRFT exponent number value, according to
The W FRFT exponent numbers value correspondence obtains the two dimensional surface of interference signal, and then obtains the three-dimensional search figure of interference signal, and
Determine the accurate order p of the three-dimensional search figure of interference signal0；W is the positive integer more than 0；
Step 5, using the accurate order p of the three-dimensional search figure of interference signal0P is carried out to radar echo signal0Rank FRFT becomes
Change, obtain p0Radar echo signal after rank FRFT conversion；
Step 6, to p0Radar echo signal after rank FRFT conversion carries out interference signal suppression treatment, obtains interference signal suppression
Radar echo signal afterwards；
Step 7, the radar echo signal after suppressing to interference signal carries out FRFT inverse transformations, obtains the radar after FRFT inverse transformations
Echo-signal, the radar echo signal after the FRFT inverse transformations is the time domain radar echo signal after interference signal suppression.
2. a kind of linear FM radar based on FRFT as claimed in claim 1 disturbs quick suppressing method, it is characterised in that
In step 1, described to extract interference signal in the radar echo signal, its process is：
Radar echo signal is received from the antenna of radar, the time-frequency of radar echo signal is obtained according to the radar echo signal
Relation distribution map；In the relationship between frequency and time distribution map of radar echo signal, axis of abscissas is the time, and axis of ordinates is frequency；
Interference signal is extracted in the relationship between frequency and time distribution map of radar echo signal, the time-frequency distributions of the interference signal are in radar echo signal
Relationship between frequency and time distribution map in be straight line, and the interference signal be linear FM signal；Wherein it is determined that n-th sampling
Interference signal at point is x (n),f0It is the carrier frequency of radar echo signal, fsFor radar is returned
The sample frequency of ripple signal, K is the chirp rate of interference signal, and K=B/T, B are the bandwidth of interference signal, and T is interference signal
Time width, n represents n-th sampled point in interference signal, n ∈ [0, NJ- 1], NJ=T × fs, NJIt is the sampling number of interference signal.
3. a kind of linear FM radar based on FRFT as claimed in claim 1 disturbs quick suppressing method, it is characterised in that
In step 2, the interference signal after the delay process is designated asIts expression formula is：
Wherein, M is that the time delay points that delay process includes are carried out to radar echo signal, M<N,E is represented and referred to
Number function, fsIt is the sample frequency of radar echo signal, K is the chirp rate of interference signal, f0It is the load of radar echo signal
Frequently, n represents n-th sampled point in interference signal, n ∈ [0, NJ- 1], NJ=T × fs, NJIt is the sampling number of interference signal.
4. a kind of linear FM radar based on FRFT as described in claim 1 or 3 disturbs quick suppressing method, and its feature exists
In the detailed process of step 3 is：
To the interference signal after delay processFast Fourier Transform (FFT) FFT is carried out, is obtained by the interference of Fast Fourier Transform (FFT)
SignalObtain by the interference signal of Fast Fourier Transform (FFT)Peak point position, and then be calculated the tune of interference signal
Frequency slope accurately estimates a,F is by the interference signal of Fast Fourier Transform (FFT)The corresponding frequency of middle peak point,
fsIt is the sample frequency of radar echo signal, M is that the time delay points that delay process includes are carried out to radar echo signal；
It is then determined that the FRFT conversion orders p of interference signal；When the FRFT of interference signal is transformed to impulse function, it is calculated
The chirp rate rough estimate u' of interference signal,Then the chirp rate rough estimate according to interference signal
U', being calculated interference signal carries out order rough estimate p required when FRFT is converted,arccot
For arc tangent is operated.
5. a kind of linear FM radar based on FRFT as described in claim 1 or 3 disturbs quick suppressing method, and its feature exists
In the detailed process of step 4 is：
Required order rough estimate p when carrying out FRFT according to interference signal, when determining that interference signal carries out accurate FRFT and converts
The excursion [p- △, p+ △] of required order, 0<△<1；
The excursion [p- △, p+ △] that required order when accurate FRFT is converted is carried out to interference signal is carried out uniformly with step-length δ
Divide, 0<δ<1；And then W FRFT exponent number value is obtained, (u, h) of interference signal is obtained according to W FRFT exponent numbers value correspondence
Two dimensional surface, u carries out corresponding quefrency domain after p ranks FRFT is converted for radar echo signal, is abbreviated as u domains；H is u domains correspondence
Range value；Wherein, w-th the w' two dimensional surface (u of the FRFT exponent numbers value correspondence interference signalw',hw'), uw'It is thunder
Corresponding the w' quefrency domain after carrying out p ranks FRFT conversion up to echo-signal, is abbreviated as the w' uw'Domain；hw'It is w'
uw'The corresponding range value in domain, { 1,2 ..., W'}, W are the total number of FRFT exponent number values, and W' is interference for w ∈ { 1,2 ..., W }, w' ∈
The two dimensional surface total number of signal；The total number of FRFT exponent number values is equal with the two dimensional surface total number of interference signal and one a pair
Should；W is the positive integer more than 0；
Then p ranks FRFT is carried out to radar echo signal respectively using W FRFT exponent numbers value to convert, respectively obtains W by p ranks
FRFT converts two dimensional surface；The two dimensional surface that the W converts by p ranks FRFT is folded as a section again
Plus, and then the three-dimensional search figure (p, u, h) of interference signal is obtained, and determine the Precise Order of the three-dimensional search figure of interference signal
Secondary is p0, p0Represent the corresponding FRFT conversion order of the corresponding Amplitude maxima point in u domains, p in the three-dimensional search figure of interference signal
Order rough estimate for needed for interference signal is carried out when FRFT is converted.
6. a kind of linear FM radar based on FRFT as claimed in claim 1 disturbs quick suppressing method, it is characterised in that
In steps of 5, by the p0Radar echo signal after rank FRFT conversion is designated as Xp0U (), its expression formula is：
Wherein, u for radar echo signal carry out p ranks FRFT conversion after corresponding quefrency domain, be abbreviated as u domains；It is radar
Echo-signal carries out the useful echo signal included after p ranks FRFT conversion,Become for radar echo signal carries out p ranks FRFT
The noise included after changing,For radar echo signal carries out the interference signal that includes after p ranks FRFT conversion.
7. a kind of linear FM radar based on FRFT as claimed in claim 6 disturbs quick suppressing method, it is characterised in that
In step 6, the radar echo signal after the interference signal suppressesIts expression formula is：
Wherein, frequency is u centered on M (u)0, the preferable bandstop filter with a width of 10Hz, u0For radar echo signal carries out p ranks
Corresponding quefrency domain centre frequency after FRFT conversion, u carries out corresponding quefrency after p ranks FRFT is converted for radar echo signal
Domain, is abbreviated as u domains；For radar echo signal carries out the useful echo signal that includes after p ranks FRFT conversion,For
Radar echo signal carries out the noise included after p ranks FRFT conversion,After p ranks FRFT conversion being carried out for radar echo signal
Comprising interference signal, Xp0U () is p0Radar echo signal after rank FRFT conversion.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN108375779A (en) * | 2018-01-16 | 2018-08-07 | 北京理工大学 | A kind of navigation neceiver disturbance restraining method based on Kalman filter |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101334469A (en) * | 2008-08-04 | 2008-12-31 | 北京理工大学 | Wind profile radar clutter suppression method based on fraction order Fourier transform |
| CN102323618A (en) * | 2011-05-19 | 2012-01-18 | 中国石油集团川庆钻探工程有限公司 | Coherent noise suppression method based on fractional order Fourier transformation |
| KR101558438B1 (en) * | 2014-04-25 | 2015-10-07 | 국방과학연구소 | Method and Apparatus for Active Target Classification and Feature Vector Extraction Using Fractional Fourier Transform |
| CN105717479A (en) * | 2016-01-25 | 2016-06-29 | 西安电子科技大学 | Single-station passive quick positioning method based on fractional order Fourier transformation |
| CN106249208A (en) * | 2016-07-11 | 2016-12-21 | 西安电子科技大学 | Signal detecting method under amplitude modulated jamming based on Fourier Transform of Fractional Order |
-
2016
- 2016-12-29 CN CN201611246628.5A patent/CN106842148B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101334469A (en) * | 2008-08-04 | 2008-12-31 | 北京理工大学 | Wind profile radar clutter suppression method based on fraction order Fourier transform |
| CN102323618A (en) * | 2011-05-19 | 2012-01-18 | 中国石油集团川庆钻探工程有限公司 | Coherent noise suppression method based on fractional order Fourier transformation |
| KR101558438B1 (en) * | 2014-04-25 | 2015-10-07 | 국방과학연구소 | Method and Apparatus for Active Target Classification and Feature Vector Extraction Using Fractional Fourier Transform |
| CN105717479A (en) * | 2016-01-25 | 2016-06-29 | 西安电子科技大学 | Single-station passive quick positioning method based on fractional order Fourier transformation |
| CN106249208A (en) * | 2016-07-11 | 2016-12-21 | 西安电子科技大学 | Signal detecting method under amplitude modulated jamming based on Fourier Transform of Fractional Order |
Cited By (19)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
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| CN111796280B (en) * | 2020-07-30 | 2023-10-27 | 哈尔滨工业大学 | ISAR micro-motion feature extraction-micro-motion target imaging integrated method |
| CN112346022A (en) * | 2020-11-03 | 2021-02-09 | 中国人民解放军海军航空大学 | Dense false target interference suppression method based on two-dimensional reduced fractional Fourier transform |
| CN112363120A (en) * | 2020-11-03 | 2021-02-12 | 中国人民解放军海军航空大学 | Frequency shift interference identification method based on two-dimensional fractional Fourier transform |
| CN113238194B (en) * | 2021-07-13 | 2021-10-08 | 中国人民解放军火箭军工程大学 | Broadband phased array radar anti-decoy interference method based on fractional domain-frequency domain processing |
| CN113238194A (en) * | 2021-07-13 | 2021-08-10 | 中国人民解放军火箭军工程大学 | Broadband phased array radar anti-decoy interference method based on fractional domain-frequency domain processing |
| CN115426235A (en) * | 2022-09-02 | 2022-12-02 | 西安电子科技大学 | Communication interference integrated signal design and processing method based on FRFT |
| CN115426235B (en) * | 2022-09-02 | 2024-04-16 | 西安电子科技大学 | FRFT-based communication interference integrated signal design and processing method |
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