67 results about "Bistatic mimo radar" patented technology

The invention belongs to the technical field of radar transceiver array amplitude phase error correction and discloses a bistatic MIMO radar transceiver array amplitude phase error correction method. The bistatic MIMO radar transceiver array amplitude phase error correction method comprises the following steps that all pulse periodical signals in back wave signals received by a bistatic MIMO radar are Y1...YQ, the transmitted waveform is expressed as S, transmitted waveform matching and column vectorization processing are conducted on the Yi...YQ respectively, eta1... etaQ are obtained, and a matrix X is formed by the eta1...etaQ; according to the four built selection matrixes J1...J4, X1...X4 are obtained; the wave reach direction and the wave departure direction of a target, and the steering vector of a transceiver array of the bistatic MIMO radar are estimated through the rotary subspace invariant algorithm; an amplitude phase error of the transceiver array of the bistatic MIMO radar is obtained.

The invention discloses an estimating method of direction of arrival of a bistatic MIMO (Multi-Input Multi-Output) radar based on a circular array, and mainly solves the problems that in the prior art, calculation is large and the direction of arrival of the circular array cannot be estimated. The realizing process comprises the steps of: 1, obtaining a cut-off Fourier coefficient of a steering vector of the array, and replacing the steering vector by the product of the Fourier coefficient and a base; 2, performing matched filtering for received data by the array to form an autocorrelation matrix and performing characteristic-decomposition for the matrix; 3, selecting a characteristic vector to form a noise sub space and obtaining a spatial zero-spectral function; 4, introducing the steering vector received to the spatial zero-spectral function, and solving an acceptance angle by polynomial rooting; and 5, introducing the acceptance angle received to the spatial zero-spectral function and solving an angle of departure by polynomial rooting. According to the estimating method of direction of arrival of the bistatic MIMO radar based on the circular array, the polynomial rooting method can be adopted to estimate the direction of arrival of the manifold MIMO radar of the circular array, spectrum peak search is avoided, calculation is low, and the estimating method of direction of arrival of the bistatic MIMO radar based on the circular array can be applied to estimating the direction of arrival of the bistatic MIMO radar.

The invention discloses a bistatic MIMO radar high-speed movement target parameter estimation method based on dual-frequency transmission. Echo signals of high-speed high-mobility targets are received through a receiving array of bistatic MIMO radar, and the echo signals of the receiving array are divided according to different carrier frequencies; conjugate multiplication is conducted on the two routes of echo data obtained through division, and whole cycle integration is conducted in a rapid time domain; Fourier conversion is conducted on the integrated data in a slow time domain, and each target speed is estimated; high-speed target matching filtering functions are set up; matching filtering is conducted on the echo signals of the receiving array to form a virtual array; the transmission angle of each target and the receiving angle of the target are estimated. The range walk of the high-speed targets is corrected according to the characteristic of the echo signals of the dual-frequency transmission MIMO radar, the problem that the parameter estimation performance is influenced by unstable factors such as Doppler spread and RCS rapid fluctuation is solved, and MIMO radar parameter estimation under the high-speed high-mobility targets is achieved.

The invention belongs to the technical field of bistatic MIMO radar imaging, and particularly relates to a bistatic MIMO radar target sparsity imaging method. The bistatic MIMO radar target sparsity imaging method comprises the following step that target imaging processing is carried out on distance doors of a bistatic MIMO radar in sequence. The target imaging processing carried out on any distance door of the bistatic MIMO radar comprises the steps of constructing a two-dimensional discrete angle space, and converting a target scene into a sparsity scene; then obtaining a receiving signal model obtained after matched filtering in the sparsity scene; setting a transmitting signal amplitude error opposite angle matrix gamma t and receiving a signal amplitude error opposite angle matrix gamma r of the bistatic MIMO radar; according to the receiving signal model obtained after the matched filtering, constructing a compressed sensing optimization model including the gamma trace constraint, wherein gamma=gamma t kronecker product gamma r; solving the compressed sensing optimization model; according to the solved result, obtaining the position where each target is located, and obtaining position imaging diagrams of all the targets.

The invention belongs to the technical field of radar signal processing, and discloses a bistatic MIMO radar high-speed target across-range-gate speed measuring and positioning method. The method comprises the following steps: acquiring L baseband echo pulse signals; compressing the pulse of the L baseband echo pulse signals to get pulse output signals, and estimating the rough estimated values of the launch azimuth angle, launch pitch angle and reception pitch angle of a target; determining the number of range gates spanned by the target based on the rough estimated values of the angles of the target; estimating the angle information and Doppler frequency of the target based on the number of range gates spanned by the target; and determining the coordinate information of the target based on the angle information of the target, and determining the speed of the target based on the Doppler frequency of the target. Under the condition that a radar target has range migration, the angle information and Doppler frequency of the radar target can be estimated accurately, and the radar target can be positioned accurately.

The invention discloses a bistatic radar localization dimension reduction clutter suppression method based on MIMO. By using a current bistatic MIMO radar distance dependence clutter suppression method, an operation amount is large and the number of needed independent identically distributed samples is high. By using the method of the invention, the above problems are mainly solved. Realization steps are characterized in that (1) a transmitted waveform is used to carry out matched filtering on echo data of the radar; (2) a localization dimension reduction matrix is constructed and dimension reduction processing is performed on the received data; (3) the data after the dimension reduction is used to estimate a clutter covariance matrix; (4) according to a space-time adaptive processing principle, an optimal weight vector is obtained; (5) the optimal weight is used to weight the data after the dimension reduction, the background clutter is suppressed and a target signal is detected. By using the method of the invention, there are the advantages that a computation complexity is low; a requirement to the number of the independent identically distributed samples is low and clutter suppression performance is good. The method can be used in bistatic radar ground target detection of the MIMO.

The invention provides an array element defect MIMO radar angle estimation method based on signal subspace reconstruction, which comprises the following steps: step 1, performing characteristic decomposition on a covariance matrix of an array element defect bistatic MIMO radar to obtain a signal subspace matrix, so as to reduce the dimension of the data matrix to be recovered, every M rows of dataform each signal subspace block matrix from top to bottom in the signal subspace matrix, and N signal subspace block matrices are formed in total, wherein M and N are the number of transmitting arrayelements and the number of receiving array elements respectively; step 2, according to the correlation among the signal subspace block matrixes, forming a low-rank block Hankel matrix from all the signal subspace block matrixes, and reconstructing the low-rank block Hankel matrix through an indefinite augmented Lagrangian multiplier method to recover the missing data in the block Hankel matrix, so as to obtain a complete signal subspace matrix; step 3, estimating the target angle by using an ESPRIT algorithm according to the complete signal subspace matrix.

The invention discloses an angle estimation method of a bistatic MIMO (Multiple-Input Multiple-Output) radar high-speed and high-maneuvering target. The angle estimation method comprises the steps of receiving an echo signal of a high-speed and high-maneuvering target by a receiving array of a bistatic MIMO (Multiple-Input Multiple-Output) radar; performing conjugate multiplication on echo of the receiving array and sending signals in different distant units; performing Fourier transform on data after performing conjugate multiplication in a fast time domain and a slow time domain in sequence; estimating a target speed according to a peak value in the step 3; extracting target slow time frequency domain components of different separation channels in a fast time frequency domain along with a target Doppler frequency value; splicing target frequency domain data in different distance gates to form virtual array data crossing a plurality of distance gates; and estimating sending angles and receiving angles of the targets by using a super-resolution algorithm. Through the angle estimation method, the influence on separation of MIMO radar channels caused due to high-speed and high-maneuvering movement of the target can be avoided; an effective virtual array can be formed by crossing the plurality of distance gates; and the problem of target angle parameter estimation of the bistatic MIMO radar under the high-speed and high-maneuvering target can be solved.

The invention discloses a high-order cumulant based bistatic MIMO (Multiple Input Multiple Output) radar parameter estimation method. A joint estimation method of DOD (Direction of Departure), DOA (Direction of Arrival) and Doppler frequency of targets under a gauss color noise background is given out according to bistatic MIMO radar echo signal characteristics through a characteristic that high-order cumulant is insensitive to gauss color noise. The high-order cumulant based bistatic MIMO radar parameter estimation method comprises constructing two opposite angle section matrixes of cross-fourth-order cumulant of output signals of adjacent matched filters through airspace and time domain information of the bistatic MIMO radar; decomposing a singular value of the opposite angle section matrixes of the four-order cumulant, estimating the number of targets, reducing dimensions through eigenvalues and eigenvectors and constructing a new matrix; obtaining joint estimation of the Doppler frequency, the DOD and the DOA of the targets through the eigenvalues and eigenvectors of the novel matrix. According to the high-order cumulant based bistatic MIMO radar parameter estimation method which is an effective bistatic MIMO radar parameter estimation method, a target parameter estimation process has no specific requirements for the number of transmission array elements and receiving array elements.

The invention provides an MIMO radar target blind detection method based on characteristic values under a correlated noise background. The method is suitable for large-array bistatic MIMO radar with the receiving and transmitting number of array elements and the snapshot number being close. The method comprises the steps that a random matrix theory is used as a tool, the defects that in the prior art, the snapshot number is insufficient and the target detection performance under the correlated noise background is lowered are overcome, and a random matrix model of observation data is established by echo signals under the correlated noise background; the ratio of the maximum characteristic value and the minimum characteristic value of an echo data covariance matrix is calculated to be used as the detection statistical magnitude; the freedom probability theory and Stieltjes conversion are used for deriving a threshold value expression of target detection under the correlated noise background; the threshold value is used as a judgment threshold for detecting a target. Simulation experiments show that the method is suitable for blind detection under the condition that a noise variance and a target scattering matrix are unknown, and the robustness of target detection under the correlated noise environment is obviously improved.

The invention discloses an angle estimation method for MIMO (Multiple-input Multiple-output) radar based on a MUSIC (Multiple Signal Classification) algorithm, which comprises the steps of building a differential covariance matrix of received array data after matched filtering, performing eigendecomposition on the covariance matrix by using a method of eigenvalue decomposition, and acquiring estimation for a noise subspace; acquiring estimation for a target angle by using a minimum value in spectrum peak search; and finally determining a true DOD value and pairing of the estimated angle through pairing calculation. The estimation method disclosed by the invention not only has an obvious inhibition effect for a Hermitian symmetry Toeplitz type of color noise of the covariance matrix and improves the precision of angle estimation for the bistatic MIMO radar, but also has low requirements for array manifolds of the MIMO radar, thereby being applicable to uniform array and nonuniform array configuration; and compared with a two-dimensional MUSIC algorithm, the angle estimation method for the bistatic MIMO radar based on the MUSIC algorithm is low in computation complexity.

The invention discloses a bistatic MIMO radar space maneuvering target tracking method capable of realizing accurate estimation and prediction of motion parameters such as the three-dimensional position and speed of space maneuvering targets. According to the method, a bistatic MIMO radar uniform circular array system is applied to space maneuvering target tracking, based on bistatic MIMO radar uniform circular array angle Doppler frequency estimation and the target state space, a measuring equation is established in a measuring right angle coordinate system for emitting and receiving uniform circular arrays according to a function relation between measuring elements and target motion state variables. A current statistics model applicable to maneuvering target tracking is employed to establish a state equation for describing the evolution of target motion parameters with time, the unscented Kalman filter algorithm applicable to nonlinear state filtering is employed to estimate the target motion parameters in real time, the target motion parameters can be predicted, and the tracking of the space maneuvering target is realized.

The invention discloses a bistatic MIMO radar uniform circular array angle and Doppler frequency estimation method. The method is mainly characterized by configuring a transmitter of a bistatic MIMO radar into a uniform circular array having M array elements and configuring a receiver thereof into a uniform circular array having N array elements respectively; enabling the M array elements in the transmitter to emit orthogonal signals and the N array elements in the receiver to receive the orthogonal signals emitted by the M array elements in the transmitter, and carrying out matched filtering to obtain radar echo signals after matched filtering and an NM*L-dimension matrix obtained through L times of snapshot accumulation, and furthermore, obtaining an M*L-dimension slice matrix form of any reception array element in the NM*L-dimension matrix; then, obtaining a transmitting direction estimation matrix, a receiving direction estimation matrix and a normalized Doppler frequency direction estimation matrix by utilizing a parallel factor algorithm; and finally, carrying out estimation by utilizing a least square algorithm to obtain azimuth angles and pitch angles of a radar target with respect to the transmitter and the receiver respectively, and the normalized Doppler frequency estimated value of the radar target.

The invention discloses a bistatic MIMO radar multi-target tracking method which achieves the purpose of dynamically tracking multiple radar targets at the same time. The method comprises the steps that 1, a signal model is set up; 2, initialization is conducted; 3, matched filtering is conducted; 4, an array response matrix is updated; 5, the current positions of the targets are determined; 6 whether it is needed to continue tracking the targets or not is judged; 7, target tracking is completed. Compared with an existing bistatic MIMO radar tracking method, the bistatic MIMO radar multi-target tracking method can be used for target locating, achieves real-time dynamic target tracking and has the advantages that the calculation complexity is low and calculation time is short, and the method can be used for achieving real-time locating and tracking of multiple motion targets through a MIMO radar.

The present invention discloses a clutter suppression method of a non-positive side-looking bistatic MIMO radar, belonging to the radar technology field. The method comprises the steps of (1) using the bistatic MIMO radar to receive the echo data on the non-positive side-looking condition; (2) constructing a clutter ridge distribution; (3) obtaining the clutter ridge distribution on the positive side-looking and non-positive side-looking conditions; (4) solving a three-dimensional linear interpolation matrix; (5) adding a noise calculation covariance in the interpolated echo data to obtain a weight vector; (6) weighting the interpolated data with an optimal weight to suppress the background clutter. The clutter suppression method of the non-positive side-looking bistatic MIMO radar of the present invention mainly solves the problems that on the non-positive side-looking condition, a clutter spectrum does not have the coplanarity any longer, and a three dimensional linear minimum variance method is not suitable any longer, and can eliminate a clutter distance dependence characteristic effectively, thereby improving a clutter suppression performance.

The invention provides an angle estimating method for a bistatic MIMO radar non-circular target under mutual coupling conditions. The method includes the following steps: a receiving array element receives mutually orthogonal non-circular signals emitted by an emitting array element, wherein, both the receiving array element and the emitting array element are uniform linear arrays with half wavelength; matched filtering is performed on the received non-circular signals through a matched filter of a receiving array element receiver; decoupling operation is performed on matched signal data, andthe decoupling operation is performed in a tensor domain; augmented tensor is constructed by utilizing a non-circular and multidimensional structure of the decoupled signal data in the tensor domain;high-order singular value decomposition is performed on the augmented tensor so that signal subspace can be obtained; and according to the obtained signal subspace, estimation is performed on the emitting angle and receiving angle of a target by combining a rotation invariant matrix, so that the angle estimation of the target can be obtained.

The invention discloses an airborne bistatic MIMO radar amplitude-phase error correcting method based on a single-distance gate; the method comprises the following steps that a receiver receives datawith the array element amplitude phase error in a distance gate, and echo data is corrected through a to-be-solved error correction matrix; the pitching angle and the azimuth angle of all clutter scattering points in a single distance gate relative to a transmitter and the receiver are calculated according to an airborne bistatic MIMO radar model, space-time three-dimensional guide vectors of allclutter scattering points are calculated by using angle information, orthogonal processing is carried out on the guide vectors, and then the projection matrix of the orthogonal complementary space ofthe clutter subspace is calculated; and the projection matrix is multiplied by the corrected data by utilizing the property of the projection matrix, and the minimum two-norm is solved, a constraint condition is constructed by using a first array element of the virtual array element as a reference array element, and an error correction matrix is obtained by utilizing constraint conditions. Compared with a traditional method, the method disclosed by the invention has the advantages that the calculation precision is higher, and the stability in a non-uniform clutter environment is increased.

The invention discloses a bistatic MIMO radar fault array element diagnosis method based on waveform similarity. A bistatic MIMO radar receiving array signal forms a virtual array composed of a plurality of virtual array elements after being subjected to matched filtering; a virtual array element output signal corresponding to a fault array element in the transmitting or receiving array does not contain target information and only contains noise, the noise and the signal have the characteristics of independence and non-correlation; therefore, the virtual array element output signal waveform corresponding to the fault array element is highly different from the output signal waveforms of other virtual array elements, namely, the cross-correlation value of the output signals of the fault array element and the rest array elements is close to zero, so that the positions of the fault array elements in the bistatic MIMO radar transmitting and receiving array can be diagnosed by comparing thewaveform similarity among the output signals of the virtual array elements. According to the method, an auxiliary array element and measurement equipment are not needed, and accurate and rapid self-diagnosis can be carried out on array elements with faults at any position under the condition of low signal to noise ratio.

The invention discloses a bistatic MIMO radar signal processing method based on distance-orientation coupling. The method mainly comprises steps that bistatic MIMO radar emission signals are respectively acquired, and bistatic MIMO radar pulse echoes within a pulse repetition period are received by N reception array elements; wavelength of the bistatic MIMO radar emission signals, array element intervals of the N MIMO radar reception array elements and bistatic MIMO radar reception wave beam directions are respectively determined; bistatic MIMO radar wave beam formation echoes with a pulse repetition period are calculated; a bistatic MIMO radar initial emission angle is set, and a bistatic MIMO radar initial space-time matching filtering echo z is calculated; a bistatic MIMO radar sampling time interval is set, target detection on the z is carried out, correction is carried out after respective initial distances of K targets are acquired, and thereby respective true distances of the K targets are acquired.

The invention belongs to the technical field of radar angle measurement, discloses an angle measurement method for a bistatic MIMO radar, and mainly solves problems that a conventional single-pulse bistatic MIMO radar are not high in estimation precision of DOD and DOA and is complex in calculation complexity. The scheme of the invention is that the method comprises the steps: enabling a transmitting antenna array element to transmit an orthogonal waveform, wherein the orthogonal waveform is reflected by a target and returns to a receiving antenna array element, and an echo signal is obtained;carrying out the beam scanning peak searching after the matched filtering and MTD filtering of the echo signal, so the DOA and DOD estimation is a two-dimensional searching process; taking a transmitter and a receiver as focuses, and building a series of distance and contour line equation sets, wherein the contour line equations provide the one-to-one corresponding relations between DOA and DOD,and the DOA and DOD estimation can be reduced to one-dimensional searching from the two-dimensional searching, thereby reducing the calculation burden and improving the estimation precision. Accordingto the invention, the additional information of distance and contour lines is added, and the DOA and DOD estimation performance is effectively improved.

The invention belongs to the field of antenna communication and particularly relates to a bistatic MIMO radar dynamic tracking method based on a cultural modem cluster searching mechanism. The bistatic MIMO radar dynamic tracking method comprises the steps of conducting snapshot group sampling and matched filtering on P spatial target signals, conducting position initialization on each modem of the cultural modem cluster searching mechanism, calculating a fitness function value of the position (shown in the description) of the ith modem, randomly selecting MR*D modems to execute a tracking mode, judging whether a maximum iteration number is achieved or not, receiving new data, estimating the departure directions and arrival directions of the targets according to the kth snapshot group data through output situational knowledge h (k) representatives if tracking is stopped, and making an MIMO radar dynamic target tracking curve. The accuracy and robustness of the method are improved, finally the problem of dynamic tracking of bistatic MIMO radar coherent targets is solved, and the performance is still good under the condition of low signal t0 noise ratio.

The invention discloses a bistatic MIMO radar angle estimation method under a joint error condition, comprising the following steps: performing matched filtering processing on data of a receiving array, and constructing one three-dimensional tensor model; then decomposing the three-dimensional tensor model by adopting a COMFAC algorithm and performing iterative computation on a receiving directionmatrix, a transmitting direction matrix and a target covariance matrix by utilizing an alternating least square method until convergence conditions are met, thus estimated values of the receiving direction matrix, the transmitting direction matrix and the target covariance matrix are obtained; and finally estimating DOD and DOA of a target by utilizing a least square method by virtue of a guidance vector of an auxiliary array element. The estimation method disclosed by the invention utilizes an array measurement multidimensional structure, so that precision of the estimation method is obviously better than that of a Reduced-MUSIC method; meanwhile, computational complexity of the estimation method is far below that of the Reduced-MUSIC method, and efficiency of the estimation method is higher than that of the Reduced-MUSIC method.

The invention discloses a bistatic MIMO radar array diagnosis method based on subspace clustering. The method comprises a step of performing eigenvalue decomposition on a virtual array covariance matrix to obtain a signal subspace and obtaining density distribution and distance characteristics of each data point in the signal subspace by using a density peak clustering algorithm according to distribution characteristics of each data point in the signal subspace, a step of selecting a clustering center by calculating a cluster center weight of each data point, dividing each data point in the signal subspace into different clusters in an unsupervised manner and determining an abnormal cluster, and a step of finally determining the positions of fault array elements in a transmitting array anda receiving array according to a data point in the abnormal cluster. By the adoption of the method, the fault array elements in the transmitting array and the receiving array can be diagnosed at thesame time, and extra test array elements or reference data are not needed.

The invention discloses a bistatic MIMO radar angle estimation method based on four-linear decomposition. According to the method, a covariance matrix of received data is estimated through utilizing the multidimensional structure of array signals, and a fourth-order tensor model of the covariance matrix is constructed; a receiving direction matrix, a transmitting direction matrix and a target covariance matrix are initialized into a unit matrix; the receiving direction matrix, the transmitting direction matrix and the target covariance matrix are iteratively calculated through utilizing the alternating least squares method till the convergence condition is met; and lastly, DOD and DOA of a target are estimated through the least squares method. Compared with a traditional algorithm, no additional calibration sources, singular value decomposition and spectral peak search are needed, the estimated DOD and DOA can be automatically matched, accuracy of parameter estimation is higher than the ESPRIT algorithm and the HOSVD algorithm, and complexity is lower than the PARAFA C algorithm.