CN113376599A - FDA distance fuzzy clutter suppression method based on mainlobe correction - Google Patents

FDA distance fuzzy clutter suppression method based on mainlobe correction Download PDF

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CN113376599A
CN113376599A CN202110071432.1A CN202110071432A CN113376599A CN 113376599 A CN113376599 A CN 113376599A CN 202110071432 A CN202110071432 A CN 202110071432A CN 113376599 A CN113376599 A CN 113376599A
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compensation
representing
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distance
correction
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CN113376599B (en
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朱圣棋
王宇卓
王可
许京伟
兰岚
贺雄鹏
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Xidian University
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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
    • G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
    • G01S7/02—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00
    • G01S7/41—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00 using analysis of echo signal for target characterisation; Target signature; Target cross-section
    • G01S7/414—Discriminating targets with respect to background clutter
    • 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
    • G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
    • G01S7/02—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00
    • G01S7/41—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00 using analysis of echo signal for target characterisation; Target signature; Target cross-section
    • G01S7/411—Identification of targets based on measurements of radar reflectivity
    • 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
    • G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
    • G01S7/02—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00
    • G01S7/41—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00 using analysis of echo signal for target characterisation; Target signature; Target cross-section
    • G01S7/418—Theoretical aspects
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
    • Y02A90/00—Technologies having an indirect contribution to adaptation to climate change
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Abstract

The invention discloses an FDA distance fuzzy clutter suppression method based on mainlobe correction, which comprises the following steps: establishing a signal model, and obtaining a radar echo signal according to the signal model; constructing a range phase compensation guide vector, and performing first compensation processing on the radar echo signal according to the range phase compensation guide vector to obtain a first echo processing signal; constructing a correction reduction compensation vector corresponding to the main lobe correction weight, and carrying out reduction compensation processing on the first echo processing signal according to the correction reduction compensation vector to obtain a compensation reduction signal; and selecting any transmitting array metadata in the compensation reduction signals to obtain a dimension reduction compensation signal, and performing secondary compensation processing on the dimension reduction compensation signal to realize suppression of radar range ambiguity clutter. The invention can distinguish signals in fuzzy areas with different distances by carrying out main lobe motion correction at the radar transmitter for recovery compensation and utilizing the distance coupling characteristic of FDA signal echoes, and inhibits distance fuzzy clutter by compensation.

Description

FDA distance fuzzy clutter suppression method based on mainlobe correction
Technical Field
The invention belongs to the technical field of radar signal processing, and particularly relates to an FDA distance fuzzy clutter suppression method based on mainlobe correction.
Background
The airborne phased array radar takes an airplane flying at high altitude as a carrier, and has the advantages of wide monitoring range, long low-altitude target early warning time and the like. Modern attacking targets are usually attacked by military through maneuvering flight, which poses serious threat to national defense systems, and how to timely and effectively realize detection and early warning of maneuvering targets is a major challenge of future radar monitoring systems.
The forward-looking array is used as a common array structure of an airborne radar, clutter distribution of the forward-looking array has distance dependency, the number of independent training samples distributed in the same way is usually limited, and the radar target detection performance is influenced. The ground clutter suppression under the downward looking operation of the forward looking array airborne radar system is one of the key problems of ground target detection. The traditional Space-Time Adaptive Processing (STAP) method utilizes spatial information of an array element antenna and Time information between coherent pulses to perform Adaptive suppression on clutter in a combined Space-Time two-dimensional mode to detect a low signal-to-noise ratio target, in a front side view array, the clutter at different distances have the same distribution characteristic in a power spectrum, and the STAP technology can effectively detect a radar target.
However, in the case of a forward looking array, radar clutter has distance dependency, that is, clutter distribution characteristics are different due to different distances, so that fuzzy non-uniform clutter is an important problem faced by an airborne forward looking array radar, and in addition, under a high repetition frequency pulse system, clutter echoes in fuzzy areas with different distances overlap when the radar enters a steady state to work. Clutter of an airborne forward-looking array radar system has distance dependency, clutter in different areas has different distribution characteristics, distance fuzzy clutter is overlapped with each other, and the observable areas of the radar can be seriously polluted, so that the radar detection performance is difficult to improve by using the STAP method.
Disclosure of Invention
In order to solve the above problems in the prior art, the present invention provides a distance ambiguity suppression method based on mainlobe correction for FDA.
One embodiment of the present invention provides a method for FDA distance ambiguity suppression based on mainlobe correction, including the following steps:
the method comprises the following steps:
step 1, establishing a signal model, and obtaining a radar echo signal according to the signal model;
step 2, constructing a range phase compensation guide vector, and performing first compensation processing on the radar echo signal according to the range phase compensation guide vector to obtain a first echo processing signal;
step 3, constructing a correction reduction compensation vector corresponding to the main lobe correction weight, and carrying out reduction compensation processing on the first echo processing signal according to the correction reduction compensation vector to obtain a compensation reduction signal;
and 4, selecting any transmitting array metadata in the compensation reduction signals to obtain a dimension reduction compensation signal, and performing secondary compensation processing on the dimension reduction compensation signal to finally realize suppression of radar range ambiguity clutter.
In one embodiment of the present invention, the radar echo signal obtained by the signal model established in step 1 is represented as:
Figure RE-GDA0003160610610000021
wherein p represents the p-th distance fuzzy area in the power range, the number of the distance fuzzy areas is U, q represents clutter blocks positioned at a certain angle in the same distance fuzzy area, and the total number of the clutter blocks is Nc，spqRepresents a clutter signal corresponding to the qth clutter block of the pth range ambiguity region,
Figure RE-GDA0003160610610000031
the representation of the noise is represented by,
Figure RE-GDA0003160610610000032
representing the main lobe correction weight vector, gamma0p＝γ0＝exp{-j2πf0R∑/c}，f0Denotes the reference frequency, R∑Representing the slope distance, c the speed of light, ppqRepresenting the product of the scattering coefficient of the illuminated radar target and the signal propagation gain in the q-th clutter block in the p-th range ambiguity region, sdRepresenting a Doppler steering vector, fpqd0Indicating the normalized Doppler frequency, s, of the q-th clutter block in the p-th range ambiguity regionrRepresenting the received spatial steering vector, fqrIndicating the q-th clutter block corresponds to the received signal angular frequency, sctRepresenting the transmit spatial steering vector, fpqctRepresenting the angular frequency, s, of the composite transmit signal for the q-th clutter block in the p-th range ambiguity regionRRepresenting the distance-coupled phase component, fRA distance fuzzy area coupling term is represented,
Figure RE-GDA0003160610610000033
Δ f denotes the frequency increment, fpRRepresenting the range-coupled phase angular frequency, s, in the p-th range ambiguity regiontRepresenting the transmit spatial steering vector, fqtRepresents the corresponding transmitting space angular frequency of the q-th clutter block,
Figure RE-GDA0003160610610000034
indicating a kronecker product, which indicates a Hamamada product.
In one embodiment of the invention, the signal s of the clutter block of the clutter signal corresponding to the qth clutter block of the p-th distance-blurred region in the step 1pqExpressed as:
Figure RE-GDA0003160610610000035
wherein, γ0＝exp{-j2πf0R∑/c}，f0Denotes the reference frequency, R∑Represents the slant distance, c represents the speed of light, p represents the product of the scattering coefficient of the illuminating radar target and the signal propagation gain,
Figure RE-GDA0003160610610000036
represents the main lobe correction weight vector, sdRepresenting a Doppler steering vector, fd0Representing normalized Doppler frequency, drIndicating the spacing between array elements in the receiving array, psirRepresenting the spatial cone angle, s, of the target and receive arraysctRepresenting the transmit spatial steering vector, fctRepresenting the composite transmitted spatial angular frequency, sRRepresenting the range-coupled phase component,
Figure RE-GDA0003160610610000037
Δ f denotes the frequency increment, srRepresenting the received spatial steering vector, frRepresenting the received spatial angular frequency, stRepresenting the transmit spatial steering vector, ftWhich represents the spatial angular frequency of the transmission,
Figure RE-GDA0003160610610000041
indicating noise, an indicates a Hamamad product,
Figure RE-GDA0003160610610000042
representing the kronecker product.
In one embodiment of the present invention, the range-phase compensation steering vector constructed in step 2 is represented as:
Figure RE-GDA0003160610610000043
wherein q isRRepresenting a range-phase compensated steering vector, fR0＝Δf2R0/c，R0Representing unambiguous distance, c light speed, Δ f frequency increment, M number of transmitting elements [ ·]TIs a transposed operation sign.
In one embodiment of the present invention, the correction reduction compensation vector corresponding to the main-lobe correction weight constructed in step 3 is represented as:
Figure RE-GDA0003160610610000044
wherein the content of the first and second substances,
Figure RE-GDA0003160610610000045
represents a correction reduction compensation vector, hK1＝[0,1,...,K-1]TK represents the number of coherent processing pulses, dr(fPRF)＝[0,j2πΔf/fPRF,...,j2π(M-1)Δf/fPRF]T，fPRFWhich is indicative of the pulse repetition frequency,
Figure RE-GDA0003160610610000046
representing an N x 1 dimensional all-one matrix, with N representing the number of elements of the receive array.
In an embodiment of the present invention, the compensated restoration signal obtained by the restoration compensation processing in step 3 is represented as:
Figure RE-GDA0003160610610000047
wherein the content of the first and second substances,
Figure RE-GDA0003160610610000048
representing a correction reduction compensation vector, eRA distance compensation term is represented as a function of distance,
Figure RE-GDA0003160610610000049
Figure RE-GDA00031606106100000410
representing a K x 1 dimensional all-one matrix,
Figure RE-GDA00031606106100000411
representing an Nx 1-dimensional all-one matrix, qR[fR0(R0)]Representing a range-phase compensated steering vector, bcThe representation represents a vector of main-lobe correction weights,
Figure RE-GDA0003160610610000051
represents the main lobe correction compensation vector bCThe corresponding frequency of the frequency is set to be,
Figure RE-GDA0003160610610000052
representing a correction restoration compensation vector
Figure RE-GDA0003160610610000053
Corresponding frequency term, fRIndicating the frequency corresponding to the distance fuzzy area coupling term,
Figure RE-GDA0003160610610000054
fPRFindicating the pulse repetition frequency.
In one embodiment of the present invention, step 4 comprises:
selecting any transmitting array element data in the compensation restoring signals to reduce the dimension of the compensation restoring signals in the NMK dimension to the dimension reduction compensating signals in the MK dimension;
and performing secondary compensation processing on the dimensionality reduction compensation signal by using a DW technology to realize suppression of radar distance fuzzy clutter.
Compared with the prior art, the invention has the beneficial effects that:
according to the FDA distance ambiguity clutter suppression method based on mainlobe correction provided by the invention, mainlobe motion correction phase weighting is carried out at a radar transmitter, the mainlobe irradiation areas of different pulses are unified, then recovery compensation is carried out at a receiving end, signals of different distance ambiguity regions can be distinguished by utilizing the distance coupling characteristic of FDA signal echoes, through compensation, the signals from an observation region are the same as the traditional MIMO signals, and the distance ambiguity signals from a non-observation region present low-gain discrete distribution in a power spectrum, so that distance ambiguity clutter is suppressed.
The present invention will be described in further detail with reference to the accompanying drawings and examples.
Drawings
Fig. 1 is a schematic flowchart of an FDA distance ambiguity suppression method based on mainlobe correction according to an embodiment of the present invention;
FIG. 2 is a schematic diagram of a geometry of an airborne forward-looking array FDA-MIMO radar provided by an embodiment of the present invention;
fig. 3 is a schematic diagram of FDA radar pulses and main lobe trends provided by an embodiment of the present invention;
fig. 4 is a schematic diagram of an FDA radar pulse time domain pattern provided by an embodiment of the present invention;
fig. 5 is a schematic diagram of FDA radar pulses and main lobe trends after main lobe walk correction provided by an embodiment of the present invention;
fig. 6 is a schematic diagram of an FDA radar pulse time domain directional diagram after main lobe walk correction according to an embodiment of the present invention;
fig. 7 is a schematic diagram illustrating processing of a received signal in the onboard FDA-MIMO bistatic radar distance ambiguity clutter suppression and dimension reduction search method according to an embodiment of the present invention;
FIG. 8 is a schematic diagram of transmitted and received pulses at different distances provided by an embodiment of the present invention;
fig. 9(a) to 9(b) are schematic diagrams of equivalent emission patterns of the FDA-MIMO radar before and after main lobe correction compensation according to the embodiment of the present invention;
10(a) -10 (b) are CAPON scan power spectra in Doppler and angular dimensions of the FDA after conventional MIMO and mainlobe correction compensation provided by embodiments of the present invention;
fig. 11(a) to 11(b) are schematic diagrams of IF curves corresponding to the conventional MIMO method when the spatial angular frequency of the clutter spectrum provided by the embodiment of the present invention is 0.
Detailed Description
The present invention will be described in further detail with reference to specific examples, but the embodiments of the present invention are not limited thereto.
Example one
Referring to fig. 1, fig. 1 is a schematic structural diagram of an FDA distance ambiguity clutter suppression method based on mainlobe correction according to an embodiment of the present invention. The embodiment provides an FDA distance ambiguity suppression method based on mainlobe correction, which includes the following steps:
step 1, establishing a signal model, and obtaining a radar echo signal according to the signal model.
Specifically, referring to fig. 2, fig. 2 shows an airborne vehicle according to an embodiment of the present inventionThe geometrical configuration schematic diagram of a forward-looking array FDA-MIMO radar is characterized in that coordinate axes xyz are mutually perpendicular in pairs to form a space coordinate system, the motion speed direction of a platform is consistent with the y-axis direction of the coordinate system, the height of the platform is H, a radar antenna is a front-side-looking one-dimensional equidistant linear array, the array is parallel to the x-axis, the azimuth angle formed by a clutter block P and an antenna array is set as theta, and the formed pitch angle is set as the pitch angle
Figure RE-GDA0003160610610000071
The number of transmitting array elements is set as M, the number of receiving array elements is set as N, the same spacing between the transmitting and receiving array elements is set as d, and the number of coherent processing pulses is set as K. In FDA-MIMO radar, at carrier frequency f of transmitted signal0For the reference frequency of the radar, the frequency transmitted by each array element differs by a certain frequency offset component, and the transmission frequencies of M array elements can be expressed as:
fm＝f0+(m-1)Δf m＝1,2,...,M (1)
where Δ f represents the frequency increment, and Δ f < f is required in equation (1)0. Similar to a conventional phased array radar, the narrow-band signal transmitted by the mth channel of the FDA-MIMO radar can be expressed as:
Figure RE-GDA0003160610610000072
where rect (-) is a rectangular window function representing the signal pulse, TpAnd sm (t) is an orthogonal waveform corresponding to the mth channel, and when an ideal orthogonal condition is met, the pulse width is represented as follows:
Figure RE-GDA0003160610610000073
then the mth array element received in the far field transmits a narrowband signal corresponding to the kth pulse represented as:
Figure RE-GDA0003160610610000074
wherein, taur2R/c represents the common two-way propagation delay from each array element of the radar to a far-field target P, and tausmThe time delay difference of the mth transmitting array element relative to the reference array element to the target is represented by (m-1) dcos psi/c, the slant distance from the reference array element to the far-field target is represented by R, the light speed is represented by c, and the space cone angle between the target and the reference array element is represented by psi. As can be taken from the figure 2, it can be seen,
Figure RE-GDA0003160610610000075
Figure RE-GDA0003160610610000076
representing f due to movement of the platformmCorresponding Doppler frequency
Figure RE-GDA0003160610610000081
v represents the speed of the movement of the platform,
Figure RE-GDA0003160610610000082
representing white gaussian noise, and having a reduction s due to the narrow-band signalm(t-τr/2-τsm)≈sm(t-τr/2), then rect [ (t- τ)r/2-τsm)/Tp]≈rect[(t-τr/2)/Tp]。
Referring to fig. 3, fig. 3 is a diagram illustrating FDA radar pulses and main lobe trend according to an embodiment of the present invention, and as shown in fig. 3, the phase accumulation amount between different pulses due to Δ f at the corresponding time T of PRI
Figure RE-GDA0003160610610000083
Different emission initial phases exist among the pulses, and the FDA radar emission directional diagram has distance (time) -angle coupling, so that the pointing angles of the main lobes of the receiving-end equivalent emission directional diagrams corresponding to different pulses can move. Referring to fig. 4, fig. 4 is a schematic diagram of an FDA radar pulse time domain directional diagram according to an embodiment of the present invention, fig. 4 shows the walking situation of three pulse main lobes of an FDA radar emission directional diagram in an angle and distance two-dimensional domain, where the pulse width is 4.76e-05 seconds, the corresponding distance is 14.2km, the PRI is 6.6e-04 seconds,corresponding to a distance of 200km, Δ f 1/2fPRFIt can be seen from fig. 4 that the first pulse and the second pulse are 30 to 0 degrees in the direction of the main lobe at 60km and 20km, and the main lobe of the second pulse is-20 to-90 degrees. Therefore, echoes between pulses are echoes at different positions, and have no coherence, so that clutter cancellation or space-time two-dimensional processing cannot be performed. Therefore, in this embodiment, by constructing a main lobe correction weight of a transmission directional diagram, which performs main lobe phase compensation on each pulse to make main lobes of different pulses irradiate at the same angle, a main lobe correction weight vector of this embodiment is specifically described
Figure RE-GDA0003160610610000084
Expressed as:
d(Δf/fPRF)＝[0,-j2πΔf/fPRF,...,-j2π(M-1)Δf/fPRF]T (5)
hK1＝[0,1,2,...,K-1]T (6)
Figure RE-GDA0003160610610000085
wherein [ ·]TRepresenting transposed operation symbols, fPRFWhich is indicative of the pulse repetition frequency,
Figure RE-GDA0003160610610000086
which represents the possible product in kronecker,
Figure RE-GDA0003160610610000087
and
Figure RE-GDA0003160610610000088
and forming a main lobe correction weight vector.
Referring to fig. 5, fig. 5 is a schematic diagram of an FDA radar pulse and a main lobe trend after main lobe walk correction according to an embodiment of the present invention, where a main lobe correction weight vector b is added to fig. 5 through a transmitting endCApplying a negative phase delay between different transmitted pulses to cancel the T-related phase component shown in the figure, so that different pulse normal figures all irradiate the sameAnd (4) an angle. Referring to fig. 6, fig. 6 is a schematic diagram of an FDA radar pulse time domain directional diagram after main lobe walk correction according to an embodiment of the present invention, fig. 6 is a schematic diagram of three pulse main lobe positions of the directional diagram after main lobe walk correction, and after main lobe walk correction is performed on a radar according to formula (7), formula (4) is rewritten as:
Figure RE-GDA0003160610610000091
the echo of the signal reflected by the far field is received, and the k-th pulse signal received by the nth receiving array element can be represented as:
Figure RE-GDA0003160610610000092
wherein, rho represents the product of the reflection coefficient of the target of the irradiation radar and the signal propagation gain, and the echo of the far-field reflection signal is received and processed by MIMO orthogonal waveform filtering.
Referring to fig. 7, fig. 7 is a schematic diagram of processing a received signal in an airborne FDA-MIMO bistatic radar range ambiguity clutter suppression and dimension reduction search method according to an embodiment of the present invention, where x in fig. 7nRepresenting the echo signal received by the nth receive channel,
Figure RE-GDA0003160610610000093
the conjugate transpose of the orthogonal waveform corresponding to the mth transmitting channel is represented, so that the mth transmitting channel of the FDA-MIMO radar transmits the echo signal of the kth pulse received by the nth receiving channel and received in the coherent processing time through sm(t-τr)exp(j2πfmt) write after matched filtering and pulse compression as:
Figure RE-GDA0003160610610000101
where ρ represents the product of the reflection coefficient of the illuminating radar target and the signal propagation gain, fdmIs frequency of
Figure RE-GDA0003160610610000102
Corresponding normalized Doppler frequency, expressed as
Figure RE-GDA0003160610610000103
Phase term coupled for distance in equation (10)
Figure RE-GDA0003160610610000104
Has common items
Figure RE-GDA0003160610610000105
So equation (10) is re-expressed as:
Figure RE-GDA0003160610610000106
since Δ f (m-1) < f0Then simplify fm＝(f0+Δfm)≈f0And fdm＝2v(f0+Δfm)cosψ/(cfPRF)≈2vf0cosψ/(cfPRF)＝fd0Thus, equation (11) is again re-expressed as:
Figure RE-GDA0003160610610000107
the snapshot array stream signal model of the received signal of this embodiment is represented as:
Figure RE-GDA0003160610610000108
wherein, γ0＝exp{-j2πf0R∑/c}，f0Denotes the reference frequency, R∑Represents the slant distance, c represents the speed of light, p represents the product of the scattering coefficient of the illuminating radar target and the signal propagation gain,
Figure RE-GDA0003160610610000109
represents the main lobe correction weight vector, sdRepresenting a Doppler steering vector, fd0Representing normalized Doppler frequency, drIndicating the spacing between array elements in the receiving array, psirRepresenting the spatial cone angle of the target and receiving array, sct representing a transmit spatial steering vector, fctRepresenting the composite transmitted spatial angular frequency, sRRepresenting the range-coupled phase component,
Figure RE-GDA00031606106100001010
Δ f denotes the frequency increment, srRepresenting the received spatial steering vector, frRepresenting the received spatial angular frequency, stRepresenting the transmit spatial steering vector, ftWhich represents the spatial angular frequency of the transmission,
Figure RE-GDA0003160610610000111
indicating noise, an indicates a Hamamad product,
Figure RE-GDA0003160610610000112
which represents the kronecker product of,
Figure RE-GDA0003160610610000113
is a MNK × 1 dimensional vector. The transmit spatial steering vector is represented as:
sct(fct)＝sR(fR)⊙st(ft) (14)
in which the distance-coupled phase component due to frequency diversity
Figure RE-GDA0003160610610000114
Expressed as:
Figure RE-GDA0003160610610000115
wherein the content of the first and second substances,
Figure RE-GDA0003160610610000116
emission angle frequency directorMeasurement of
Figure RE-GDA0003160610610000117
Expressed as:
Figure RE-GDA0003160610610000118
wherein the content of the first and second substances,
Figure RE-GDA0003160610610000119
receiving a spatial steering vector
Figure RE-GDA00031606106100001110
Expressed as:
Figure RE-GDA00031606106100001111
wherein the content of the first and second substances,
Figure RE-GDA00031606106100001112
doppler steering vector
Figure RE-GDA00031606106100001113
Can be expressed as:
sd(fd0)＝[1,exp{j2πfd0},...,exp{j2π(K-1)fd0}]T (18)
wherein f isd0＝2vf0cosψ/(cfprf)。bCThe phase term present due to the transmit mainlobe correction compensation amount is represented in vector form according to equation (7) as:
Figure RE-GDA00031606106100001114
wherein lK1＝[1,exp{1},exp{2},...,exp{(K-1)}]T，
Figure RE-GDA00031944162800001114
Is an N × 1 dimensional all-one matrix.
In this embodiment, only echoes of all transmitting array elements received by one receiving channel are considered, and taking the first receiving channel as an example, a signal s of a clutter block of a clutter signal corresponding to a qth clutter block of a pth range ambiguity region is receivedpqExpressed as:
Figure RE-GDA00031606106100001116
referring to fig. 8, fig. 8 is a schematic diagram of transmitted and received pulses at different distances according to an embodiment of the present invention, where K is set as the number of coherent pulses to be 5, and fig. 8 is a specific diagram of a primary ambiguity region clutter and an ambiguity-free distance R0The time domain pulse echo diagram of the region clutter is characterized in that a rectangle represents a signal and a clutter echo in an unambiguous region, and a semicircle represents a first ambiguity distance R1The echo, the echo number and the number of the transmitted pulse of the region correspond. As can be seen from fig. 8, the range ambiguity clutter in different areas at the receiving end overlap, which reduces the detection performance of the radar. Then the radar echo signal received in this embodiment is represented as:
Figure RE-GDA0003160610610000121
wherein p represents the p-th distance fuzzy area in the power range, the number of the distance fuzzy areas is U, q represents clutter blocks positioned at a certain angle in the same distance fuzzy area, and the total number of the clutter blocks is Nc，spqRepresents a clutter signal corresponding to the qth clutter block of the pth range ambiguity region,
Figure RE-GDA0003160610610000122
the representation of the noise is represented by,
Figure RE-GDA0003160610610000123
representing the main lobe correction weight vector, gamma0p＝γ0＝exp{-j2πf0R∑/c}，f0Denotes the reference frequency, R∑Representing the slope distance, c the speed of light, ppqRepresenting the product of the scattering coefficient of the illuminated radar target and the signal propagation gain in the q-th clutter block in the p-th range ambiguity region, sdRepresenting a Doppler steering vector, fpqd0Indicating the normalized Doppler frequency, s, of the q-th clutter block in the p-th range ambiguity regionrRepresenting the received spatial steering vector, fqrIndicating the q-th clutter block corresponds to the received signal angular frequency, sctRepresenting the transmit spatial steering vector, fpqctRepresenting the angular frequency, s, of the composite transmit signal for the q-th clutter block in the p-th range ambiguity regionRRepresenting the distance-coupled phase component, fRA distance fuzzy area coupling term is represented,
Figure RE-GDA0003160610610000124
Δ f denotes the frequency increment, fpRRepresenting the range-coupled phase angular frequency, s, in the p-th range ambiguity regiontRepresenting the transmit spatial steering vector, fqtRepresents the corresponding transmitting space angular frequency of the q-th clutter block,
Figure RE-GDA0003160610610000125
indicating a kronecker product, which indicates a Hamamada product.
And 2, constructing a range and phase compensation guide vector, and performing primary compensation processing on the radar echo signal according to the range and phase compensation guide vector to obtain a first echo processing signal.
Specifically, for different fuzzy or non-fuzzy areas, the embodiment specifically constructs a range-phase compensation steering vector by using a quadratic range compensation method, and performs a first compensation process on a radar echo signal corresponding to a transmission space steering vector according to the constructed range-phase compensation steering vector to obtain a first echo processed signal. Distance phase compensation guide vector constructed by the present embodiment:
Figure RE-GDA0003160610610000131
Figure RE-GDA0003160610610000132
wherein q isRRepresenting a range-phase compensated steering vector, fR0＝Δf2R0/c，R0Representing unambiguous distance, c light speed, Δ f frequency increment, M number of transmitting elements [ ·]TIs a transposed operation sign. After the formula (22) and the formula (23) are substituted into the formula (21) for compensation, the echo emission space steering vector of the unambiguous region is consistent with that of the traditional MIMO, the ambiguous region still has a distance coupling phase term, and the unambiguous region is distinguished. Taking echo signals of the kth pulse of the mth transmitting array element and the nth receiving array element as an example, echo signals of the non-ambiguity region are represented as follows:
Figure RE-GDA0003160610610000133
the primary range-blurred region echo signal is represented as:
Figure RE-GDA0003160610610000134
wherein R is1＝Ru+R0。
And 3, constructing a correction reduction compensation vector corresponding to the main lobe correction weight, and carrying out reduction compensation processing on the first echo processing signal according to the correction reduction compensation vector to obtain a compensation reduction signal.
Specifically, after the total echo signal is subjected to the first compensation processing in step 2, signals in the ambiguity-free region and the first-time distance ambiguity region still contain the equivalent transmission pattern main lobe correction compensation term. And constructing a correction reduction compensation vector corresponding to the main lobe correction weight, and performing reduction compensation on the first echo processing signal to obtain a compensation reduction signal. The specifically constructed correction reduction compensation vector corresponding to the main lobe correction weight is represented as:
dr(fPRF)＝[0,j2πΔf/fPRF,...,j2π(M-1)Δf/fPRF]T (26)
hK1＝[0,1,...,K-1]T (27)
Figure RE-GDA0003160610610000141
the equations (26), (27) and (28) are respectively substituted into the equations (24) and (25) for compensation, and the echo signal of the non-fuzzy area is represented again as:
Figure RE-GDA0003160610610000142
the range-blurred region echo signal is re-represented as:
Figure RE-GDA0003160610610000143
after two compensations, i.e. the first compensation process of step 2 and the reduction compensation process of step 3, since
Figure RE-GDA0003160610610000151
The range-blurred region echo in this embodiment can be further expressed as:
Figure RE-GDA0003160610610000152
wherein, let α be mod5|(k-1)+4|-(k-1)+1＝mod5I k +3 i-k +2, it can be seen that after twice compensation, the echo of the signal in the range-free fuzzy region is the same as that of the MIMO radar, and can be written as
Figure RE-GDA0003160610610000153
(i.e., when k is 1, 2, 3, 4, 5, respectively, α is 0, 0, 0, 0, 0), the range ambiguity clutter region is written once as
Figure RE-GDA0003160610610000154
(when k is 1, 2, 3, 4, 5, respectively, corresponding to α is 5, 0, 0, 0, 0).
With the combination of the formula (21) and the formula (28), the first echo processed signal after the receiving end compensation in this embodiment is represented as:
Figure RE-GDA0003160610610000155
wherein the content of the first and second substances,
Figure RE-GDA0003160610610000161
representing a correction reduction compensation vector, eRA distance compensation term is represented as a function of distance,
Figure RE-GDA0003160610610000162
Figure RE-GDA0003160610610000163
representing a K x 1 dimensional all-one matrix,
Figure RE-GDA0003160610610000164
representing an Nx 1-dimensional all-one matrix, qR[fR0(R0)]Representing a range-phase compensated steering vector, bCThe representation represents a vector of main-lobe correction weights,
Figure RE-GDA0003160610610000165
represents the main lobe correction compensation vector bCThe corresponding frequency of the frequency is set to be,
Figure RE-GDA0003160610610000166
representing a correction restoration compensation vector
Figure RE-GDA0003160610610000167
Corresponding frequency term, fRIndicating the frequency corresponding to the distance fuzzy area coupling term,
Figure RE-GDA0003160610610000168
fPRFindicating the pulse repetition frequency. Distance compensation term e of the present embodimentR(fR0) By adding the Hammond product to the transmission steering vector distance coupling phase term, the transmission steering vector distance coupling, frequency
Figure RE-GDA0003160610610000169
Terms coupled to the number of distance-blurred regions, and then compensated with the main-lobe correction vector bCCorresponding frequency term
Figure RE-GDA00031606106100001610
And correcting the restored compensation vector bRCFrequency term of
Figure RE-GDA00031606106100001611
Add to obtain alphapA coupled phase term that is related to the number of ambiguity regions.
And 4, selecting any transmitting array metadata in the compensation reduction signals to obtain a dimension reduction compensation signal, and performing secondary compensation processing on the dimension reduction compensation signal to realize suppression of radar range ambiguity clutter.
Specifically, any one of the compensation reducing signals is selected to reduce the dimension of the NMK compensation reducing signal to an MK dimension reduction compensation signal, the original NMK dimension data is subjected to dimension reduction to obtain MK dimension data, and clutter data dependent compensation, namely second compensation processing, is performed on the dimension reduction compensation signal by using Doppler shift technology (DW for short) and the like to realize suppression of distance fuzzy clutter of the forward looking array radar.
In order to verify the effectiveness of the FDA distance ambiguity clutter suppression method based on mainlobe correction proposed in this embodiment, the following simulation experiment is used to further prove the effectiveness of the FDA distance ambiguity clutter suppression method based on mainlobe correction.
Comparing the traditional FDA radar with the method provided by the invention in different pulse emission directional diagrams in distance and angle domains, and analyzing the change of the equivalent emission directional diagram after the main lobe correction compensation. Simulation parameters in the simulation process of the present embodiment are shown in table 1.
TABLE 1 simulation parameter List
Parameter name Parameter value
Linear array element number (M/N) 20
Carrier frequency f0 1.2GHz
Array element spacing d 0.0625m
Platform velocity 150m/s
Maximum unambiguous distance 50km
Noise to noise ratio 30dB
Signal to noise ratio 40dB
Height of platform 6km
Desired target distance 20km
Desired target angle 30°
Pulse repetition frequency PRF 3000Hz
Number of coherent pulses K 5
Simulation 1:
referring to fig. 9(a) to 9(b), fig. 9(a) to 9(b) are schematic diagrams of equivalent emission patterns of the FDA-MIMO radar before and after main lobe correction compensation according to the embodiment of the present invention, fig. 9(a) shows the equivalent emission patterns of the FDA-MIMO radar before and after main lobe correction compensation, fig. 9(b) shows the equivalent emission patterns of the FDA-MIMO radar after main lobe correction compensation, fig. 9(a) shows the pattern having coupling of distance angles, so that the main lobe is S-shaped in an angular distance two-dimensional region, fig. 9(a) shows the pattern main lobe distribution of three consecutive pulse periods, the pulse width is 4.76e-05S, the corresponding distance is 14.29km, the pulse repetition interval is 6.67e-04S, the corresponding distance is 200km, and it can be seen from observing fig. 9(a) that the high gain angle of the main lobe of the pattern of the first pulse period is between 0 degrees and 30 degrees, since carrier frequencies of different array elements of the FDA-MIMO radar are different, after accumulation of one pulse repetition interval, when a second pulse is transmitted, initial phases of the array elements are different (as shown in fig. 9, an mth array element accumulates an initial phase of 2 pi m Δ fT), and an FDA-MIMO directional diagram has an S-type distance angle coupling distribution characteristic, so that a main lobe high gain angle of the directional diagram is located at-23 degrees to-110 degrees in a second pulse period, because of an angle periodicity, in the diagram, [ -90, -110] is shown at [70,90] positions, and Δ f is 1/(2T) in simulation, at a third pulse period, an mth array element accumulates an initial phase of 2 pi m Δ f2T is 2 pi m, and initial phases of the array elements are the same, so that the situation is the same as that of the first pulse period. Fig. 9(b) shows an equivalent emission pattern of the FDA-MIMO radar after main lobe correction compensation, and it can be known from formula (7) that the first pulse period initial phase compensation is 0, so that the same as fig. 9(a), the second pulse period mth array element compensation amount is 2 pi m Δ fT, which is the same as the Δ f accumulation initial phase, so that the pattern is the same as the first pulse period, and similarly, the third pulse period is also the same as the first pulse period after compensation.
Simulation 2:
referring to fig. 10(a) to 10(b), fig. 10(a) to 10(b) are CAPON scanning power spectrums of the FDA in doppler and angle dimensions after the calibration compensation of the conventional MIMO and the mainlobe according to the embodiment of the present invention, in this embodiment, ground clutter at different distances are simulated, a forward-looking array airborne platform echo is simulated, and a clutter power spectrum diagram is drawn, specifically, fig. 10(a) is a CAPON scanning power spectrum of the conventional MIMO in doppler and angle dimensions, and fig. 10(b) is a CAPON scanning power spectrum of the FDA in doppler and angle dimensions after the mainlobe compensation according to the present invention. Because the platform is a single-base platform, the receiving angles of the transmitting angle domain are consistent, the abscissa in the figure is a Doppler domain, the ordinate is a transmitting angle domain, and clutter echoes exist in the positions of a non-fuzzy region R (20 km) and a first distance fuzzy region R (70 km) in simulation. Because of the foresight array, the clutter is distributed in a regular ellipse, and as can be seen from fig. 10(a), the clutter has a distance dependence characteristic, the echo shapes of the clutter at different distances are different, the clutter at two distances are overlapped together, and the degree f is 0dThe depression existing due to the different clutter shapes in different fuzzy regions can be seen near 0.4. It can be seen from fig. 10(b) that only the unambiguous region R0 exhibits clutter, whereas the clutter of the first ambiguous region R1 is suppressed, comparing fig. 10(a) and 10(b), at fdThe gain at the position is increased by the discrete distribution of the distance blurring clutter near 0.4 and above and below the clutter ring, and is changed from-80 dB to-60 dB to-70 dB.
Simulation 3:
referring to fig. 11(a) to 11(b), fig. 11(a) to 11(b) are schematic diagrams of IF curves corresponding to the conventional MIMO method when the spatial angular frequency of the clutter spectrum provided by the embodiment of the present invention is 0, in the embodiment, the clutter suppression effect of the present invention is compared through radar Improvement Factor (IF) index evaluation, and the IF curve is an index for evaluating radar effectiveness, and is defined as a ratio of output signal to noise ratio to input signal to noise ratio:
Figure RE-GDA0003160610610000191
wherein the content of the first and second substances,
Figure RE-GDA0003160610610000192
which is indicative of the power of the output signal,
Figure RE-GDA0003160610610000193
which is indicative of the power of the input signal,
Figure RE-GDA0003160610610000194
which is indicative of the output noise power,
Figure RE-GDA0003160610610000195
representing the input noise power, s the signal vector, w the receiver steering vector, Q the noise covariance matrix, tr (-) the trace of the matrix, (.)*Indicating that conjugation was taken.
Due to the existence of range ambiguity clutter, the clutter ridge is severely widened in Doppler and angle domains, and the target detection performance is reduced. Fig. 11(b) is an enlarged view of fig. 11(a), and the observation result shows that the clutter suppression effect can be greatly improved by the method provided by the invention. Due to clutter echoes of the distance ambiguity region and the first distance ambiguity region, the intermediate frequency curve of the conventional MIMO radar of fig. 11(b) has two notches at 0.88 and 0.93, a notch at 0.88 is caused by clutter of the distance ambiguity region, and a notch at 0.93 is caused by clutter of the first distance ambiguity region, and under the condition that the distance ambiguity clutter exists, the performance of the conventional MIMO radar is significantly reduced in the region between the position of the clutter notch point and the clutter notch, so that the larger the clutter notch is, the wider the pollution range of radar detection is, and the more significant the performance reduction is. The method provided by the invention can effectively inhibit distance fuzzy clutter outside the non-fuzzy region, the IF curve of the mainlobe correction FAD in fig. 11(b) only has one notch at 0.88, which is caused by the clutter of the non-fuzzy region, and the width of the formed notch is smaller than that of the traditional MIMO method, which shows that the notch can obviously reduce clutter expansion in the power spectrum, therefore, the method provided by the invention inhibits the distance fuzzy clutter, reduces the area of radar performance loss, and improves the detection performance.
In summary, in the method for suppressing distance ambiguity clutter based on mainlobe correction provided in this embodiment, mainlobe motion correction phase weighting is performed at a radar transmitter, so as to unify mainlobe irradiation areas of different pulses, then recovery compensation is performed at a receiving end, and signals in different distance ambiguity regions can be distinguished by using the distance coupling characteristic of FDA signal echoes, and through compensation, signals from an observation region are the same as conventional MIMO signals, while distance ambiguity signals from a non-observation region exhibit low-gain discrete distribution in a power spectrum, so as to suppress distance ambiguity clutter.
The foregoing is a more detailed description of the invention in connection with specific preferred embodiments and it is not intended that the invention be limited to these specific details. For those skilled in the art to which the invention pertains, several simple deductions or substitutions can be made without departing from the spirit of the invention, and all shall be considered as belonging to the protection scope of the invention.

Claims (7)

1. A distance ambiguity noise suppression method based on main lobe correction for FDA is characterized by comprising the following steps:
step 1, establishing a signal model, and obtaining a radar echo signal according to the signal model;
step 2, constructing a range phase compensation guide vector, and performing first compensation processing on the radar echo signal according to the range phase compensation guide vector to obtain a first echo processing signal;
step 3, constructing a correction reduction compensation vector corresponding to the main lobe correction weight, and carrying out reduction compensation processing on the first echo processing signal according to the correction reduction compensation vector to obtain a compensation reduction signal;
and 4, selecting any transmitting array metadata in the compensation reduction signals to obtain a dimension reduction compensation signal, and performing secondary compensation processing on the dimension reduction compensation signal to finally realize suppression of radar range ambiguity clutter.
2. The FDA distance ambiguity clutter suppression method based on mainlobe correction according to claim 1, wherein the radar echo signal corresponding to the signal model established in step 1 is represented as:
Figure RE-FDA0003160610600000011
wherein p represents the p-th distance fuzzy area in the power range, the number of the distance fuzzy areas is U, q represents clutter blocks positioned at a certain angle in the same distance fuzzy area, and the total number of the clutter blocks is Nc，spqRepresents a clutter signal corresponding to the qth clutter block of the pth range ambiguity region,
Figure RE-FDA0003160610600000012
the representation of the noise is represented by,
Figure RE-FDA0003160610600000013
represents the primary lobe correction weight vector, γ0p＝Υ0＝exp{-j2πf0R∑/c}，f0Denotes the reference frequency, R∑Representing the slope distance, c the speed of light, ppqRepresenting the product of the scattering coefficient of the illuminated radar target and the signal propagation gain in the q-th clutter block in the p-th range ambiguity region, sdRepresenting a Doppler steering vector, fpqd0Indicating the normalized Doppler frequency, s, of the q-th clutter block in the p-th range ambiguity regionrRepresenting the received spatial steering vector, fqrIndicating the q-th clutter block corresponds to the received signal angular frequency, sctRepresenting the transmit spatial steering vector, fpqctRepresenting the angular frequency, s, of the composite transmit signal for the q-th clutter block in the p-th range ambiguity regionRRepresenting the distance-coupled phase component, fRA distance fuzzy area coupling term is represented,
Figure RE-FDA0003160610600000021
Δ f denotes the frequency increment, fpRRepresenting the range-coupled phase angular frequency, s, in the p-th range ambiguity regiontRepresenting the transmit spatial steering vector, fqtRepresents the corresponding transmitting space angular frequency of the q-th clutter block,
Figure RE-FDA0003160610600000022
indicating a kronecker product, which indicates a Hamamada product.
3. The method of claim 2, wherein the signal s of the clutter signal clutter block corresponding to the qth clutter block of the pth distance ambiguity region is the signal s of the FDA distance ambiguity clutter block based on mainlobe correctionpqExpressed as:
Figure RE-FDA0003160610600000023
wherein, γ0＝exp{-j2πf0R∑/c}，f0Denotes the reference frequency, R∑Represents the slant distance, c represents the speed of light, p represents the product of the scattering coefficient of the illuminating radar target and the signal propagation gain,
Figure RE-FDA0003160610600000024
represents the main lobe correction weight vector, sdRepresenting a Doppler steering vector, fd0Representing normalized Doppler frequency, drIndicating the spacing between array elements in the receiving array, psirRepresenting the spatial cone angle, s, of the target and receive arraysctRepresenting the transmit spatial steering vector, fctRepresenting the composite transmitted spatial angular frequency, sRRepresenting the range-coupled phase component,
Figure RE-FDA0003160610600000025
Δ f denotes the frequency increment, srRepresenting the received spatial steering vector, frRepresenting the received spatial angular frequency, stRepresenting the transmit spatial steering vector, and,ftwhich represents the spatial angular frequency of the transmission,
Figure RE-FDA0003160610600000026
indicating noise, an indicates a Hamamad product,
Figure RE-FDA0003160610600000027
representing the kronecker product.
4. The method of claim 3, wherein the distance-phase compensation guide vector constructed in step 2 is expressed as:
Figure RE-FDA0003160610600000028
wherein q isRRepresenting a range-phase compensated steering vector, fR0＝Δf2R0/c，R0Representing unambiguous distance, c light speed, Δ f frequency increment, M number of transmitting elements [ ·]TIs a transposed operation sign.
5. The method of claim 4, wherein the correction reduction compensation vector constructed in step 3 corresponding to the mainlobe correction weight is expressed as:
Figure RE-FDA0003160610600000031
wherein the content of the first and second substances,
Figure RE-FDA0003160610600000032
represents a correction reduction compensation vector, hK1＝[0,1,...,K-1]TK represents the number of coherent processing pulses, dr(fPRF)＝[0,j2πΔf/fPRF,...,j2π(M-1)Δf/fPRF]T，fPRFWhich is indicative of the pulse repetition frequency,
Figure RE-FDA0003160610600000033
representing an N x 1 dimensional all-one matrix, with N representing the number of elements of the receive array.
6. The method for FDA distance ambiguity suppression based on mainlobe correction according to claim 5, wherein the compensated reduction signal obtained by the reduction compensation process in step 3 is represented as:
Figure RE-FDA0003160610600000034
wherein the content of the first and second substances,
Figure RE-FDA0003160610600000035
representing a correction reduction compensation vector, eRA distance compensation term is represented as a function of distance,
Figure RE-FDA0003160610600000036
Figure RE-FDA0003160610600000037
representing a K x 1 dimensional all-one matrix,
Figure RE-FDA0003160610600000038
representing an Nx 1-dimensional all-one matrix, qR[fR0(R0)]Representing a range-phase compensated steering vector, bcThe representation represents a vector of main-lobe correction weights,
Figure RE-FDA0003160610600000039
represents the main lobe correction compensation vector bCThe corresponding frequency of the frequency is set to be,
Figure RE-FDA00031606106000000310
representing a correction restoration compensation vector
Figure RE-FDA00031606106000000311
Corresponding frequency term, fRIndicating the frequency corresponding to the distance fuzzy area coupling term,
Figure RE-FDA00031606106000000312
fPRFindicating the pulse repetition frequency.
7. The method of claim 6, wherein step 4 comprises:
selecting any transmitting array element data in the compensation restoring signals to reduce the dimension of the compensation restoring signals in the NMK dimension to the dimension reduction compensating signals in the MK dimension;
and performing secondary compensation processing on the dimensionality reduction compensation signal by using a DW technology to finally realize the suppression of the radar distance fuzzy clutter.
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114265018A (en) * 2022-02-28 2022-04-01 西安电子科技大学 Short-range clutter suppression method based on multi-frequency split radar
CN114966675A (en) * 2022-05-25 2022-08-30 苏州威陌电子信息科技有限公司 MIMO array rapid imaging method based on distance compensation

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2000147100A (en) * 1998-11-16 2000-05-26 Mitsubishi Electric Corp Pulse doppler radar apparatus
WO2018045566A1 (en) * 2016-09-09 2018-03-15 深圳大学 Random pulse doppler radar angle-doppler imaging method based on compressed sensing
CN108761419A (en) * 2018-06-15 2018-11-06 中国民航大学 Low level wind shear velocity estimation method based on combination main channel self-adaptive processing when empty
CN110703209A (en) * 2019-09-30 2020-01-17 西安电子科技大学 Method for suppressing ground distance fuzzy clutter of high repetition frequency airborne forward looking array radar

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2000147100A (en) * 1998-11-16 2000-05-26 Mitsubishi Electric Corp Pulse doppler radar apparatus
WO2018045566A1 (en) * 2016-09-09 2018-03-15 深圳大学 Random pulse doppler radar angle-doppler imaging method based on compressed sensing
CN108761419A (en) * 2018-06-15 2018-11-06 中国民航大学 Low level wind shear velocity estimation method based on combination main channel self-adaptive processing when empty
CN110703209A (en) * 2019-09-30 2020-01-17 西安电子科技大学 Method for suppressing ground distance fuzzy clutter of high repetition frequency airborne forward looking array radar

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
王宇卓;朱圣棋;许京伟;: "MIMO双基地机载雷达距离模糊杂波抑制方法", 雷达学报, no. 02 *
田明明;廖桂生;李云鹏;朱圣棋;: "超高速平台载雷达杂波特性与抑制方法", 系统工程与电子技术, no. 02 *
许京伟;廖桂生;: "前视阵FDA-STAP雷达距离模糊杂波抑制方法", 雷达学报, no. 04 *

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114265018A (en) * 2022-02-28 2022-04-01 西安电子科技大学 Short-range clutter suppression method based on multi-frequency split radar
CN114966675A (en) * 2022-05-25 2022-08-30 苏州威陌电子信息科技有限公司 MIMO array rapid imaging method based on distance compensation
CN114966675B (en) * 2022-05-25 2023-09-05 苏州威陌电子信息科技有限公司 MIMO array rapid imaging method based on distance compensation

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