62 results about "Virtual array" patented technology

The invention belongs to the crossing field of information and ocean science and technology, and discloses a DOA estimation method for a UUV broadside parallel co-prime array. According to the method, firstly, a virtual extension array is generated by utilizing an array auto-covariance and cross-covariance matrix, then, Toeplitz completion is carried out on'holes' in the virtual array through trace norm regularization and nuclear norm regularization constraints, a complete covariance structure is recovered, and finally, an extension matrix is constructed, and rotation invariance of a signal subspace of the extension matrix is utilized, so that the covariance structure of the virtual array is obtained. The pitch angle and the azimuth angle of the target are jointly solved, automatic angle pairing is achieved, and the effectiveness and the reliability of the method are verified through simulation results. According to the method, aiming at the application challenges that the UUV broadside array space is limited and the underwater environment is complex, all virtual array elements of the broadside parallel co-prime array are fully utilized, the array freedom degree and estimation precision are remarkably improved, the target detection capacity of the UUV is effectively enhanced, and the method has high practical engineering application value.

The invention discloses a real-time positioning method, system and device supporting multi-frequency Beidou signals and a medium. The method comprises the steps that multi-frequency observation is collected in parallel, and quality features are generated; performing distribution alignment of risk perception based on the quality features to obtain equivalent observation; generating a causal weight by adopting anti-fact evaluation based on influence approximation; in the cross-frequency fusion model, taking multiple paths as potential disturbance quantities, only implementing group stripping on suspicious stars, frequencies or time periods, and solving and outputting a positioning result in combination with robust constraint and increment; a confidence radius is generated on line, the confidence radius is used as a main control signal to execute risk-driven self-adaptive control, and the risk-driven self-adaptive control comprises weight adjustment, measurement subset selection and front-end loop and frequency chain working state adjustment; and implementing topological consistency goalkeeping on a multi-frequency phase level, and triggering time domain virtual array suppression and feeding back to the fusion model when abnormity occurs. The system can significantly improve the precision, robustness and integrity of Beidou multi-frequency real-time positioning.

The invention relates to a two-dimensional staggered array MIMO (Multiple Input Multiple Output) radar system for monitoring dynamic deformation of a bridge, which realizes decoupling of spatial resolution and time resolution by adopting a two-dimensional staggered array MIMO radar hardware architecture and replacing traditional mobile synthetic aperture with static virtual aperture synthesis through integrated design. According to the system, a continuous virtual area array is synthesized through transmitting and receiving arrays which are in non-uniform sparse arrangement, and high-resolution three-dimensional imaging of a bridge monitoring area is realized in combination with an FMCW signal processing and near-field three-dimensional imaging algorithm; and carrying out pixel-level processing on the serialized three-dimensional complex image by using a rapid time sequence interference and deformation extraction module to obtain a high-precision deformation sequence. The method does not need a mechanical scanning part, has the advantages of high environmental robustness, low hardware cost, flexible deployment and the like, and can provide panoramic and high-precision four-dimensional dynamic deformation field data for bridge structure state evaluation.

The invention discloses a TDM-MIMO radar Doppler phase offset compensation method based on iteration, and the method comprises the steps: carrying out the equivalent conversion of a TDM-MIMO radar model into a one-transmitting-multiple-receiving virtual array model, building a signal receiving model of a virtual array, and obtaining a beat signal; constructing a target echo space-time joint matrix; constructing an airspace signal vector based on the target initial Doppler frequency; and performing iterative estimation on target angle estimation and Doppler frequency, and estimating the angle by using a phase offset compensation result. According to the method, the Doppler frequency is scanned more meticulously by constructing the Doppler frequency scanning manifold matrix, the Doppler frequency dimension and the angle dimension are decoupled, the space-time combined two-dimensional estimation is converted into two one-dimensional estimation, and the accurate Doppler frequency and angle are obtained after few times of iteration.

The spatial resolution of the virtual array antenna and the accuracy of the virtual array antenna's target direction estimation are adjusted according to the purpose. [Solution] The antenna device according to the embodiment comprises a reference signal generation unit, a first module, a second module, and a phase value generation unit. The phase value generation unit generates a first phase value based on the phase difference of the received signals in at least two virtual antennas, which are formed based on the received signals received by at least a portion of the first receiving antenna and the second receiving antenna when the first transmitting antenna transmits a transmission signal based on the first reference signal. The first transmission processing circuit shifts the phase of the second reference signal, which is transmitted by the second transmitting antenna after the first transmitting antenna, by the first phase value.

Provided are a signal transmission method, a communication apparatus, a storage medium and a program product. The method comprises: determining array elements in a coprime array, wherein the array elements in the coprime array are some array elements in an antenna array of a first communication apparatus; and on the basis of hybrid beamforming, transmitting a first signal by means of the coprime array. The coprime array can achieve a larger virtual aperture by means of fewer physical array elements, or in other words, the number of equivalent virtual array elements is usually greater than the number of physical array elements. In this way, a transmitter of the first signal can use fewer array elements to implement beamforming of more signals; and a receiver of the first signal can use fewer array elements to implement DOA estimation of more signals, thereby improving the degrees of freedom of DOA estimation.

The invention discloses a resolution-oriented 4D millimeter wave radar antenna array and physical layout collaborative optimization method, a program, equipment and a storage medium, which are suitable for a radar system with a limited space and a multi-chip structure. The method comprises the steps of firstly collecting system input parameters; then, an antenna design constraint model is constructed, spatial discretization is carried out, and an optimizable matrix model is formed; transmitting and receiving array structures in the azimuth angle direction and the pitch angle direction are jointly designed through a virtual array mapping strategy, so that the requirements of MIMO mapping efficiency maximization and target angle resolution are met. After an antenna structure is determined, an optimization objective function is further constructed based on strong constraint and soft constraint, and an antenna layout scheme which meets the manufacturing requirements and has optimal performance is obtained through a traversal and search method. According to the method, the virtual aperture can be effectively improved, the antenna number redundancy is reduced, the wiring accessibility is optimized, and the resolution and engineering realizability of a 4D radar system are enhanced.

This invention belongs to the field of information and marine technology, and discloses a method for estimating the DOA (Direction of Aperture) of a UUV (Ultra-UV) hull-side array using conjugate enhancement and virtual extension. This method performs conjugate enhancement processing on the received signal from a parallel coprime array, calculates the augmented statistical matrix including autocorrelation, conjugate autocorrelation, cross-correlation, and conjugate cross-correlation, and constructs an extended correlation matrix through weighted combination. A virtual uniform linear array is constructed using the differential co-array characteristics of the coprime array. A redundant integration matrix is ​​designed to remove redundancy from the covariance matrix, obtaining the equivalent signal of the virtual array. Then, the covariance matrix of the virtual array with a Toeplitz structure is reconstructed. Finally, a dual rotation-invariant subspace algorithm is used to achieve high-precision, automatic pairing estimation of the underwater target's azimuth and pitch angles. This invention extends the array aperture, improves the estimation robustness in low signal-to-noise ratio environments, and eliminates the need for spectral peak search, providing technical support for UUV underwater target positioning.

A method for sharing reconfigurable array modes in a MIMO frequency-modulated millimeter-wave radar array is proposed. Based on the echo signal data matrices obtained after analog-to-digital conversion of different modes, range-dimensional Fast Fourier Transform (FFT) and velocity-dimensional FFT are performed on them respectively to obtain the range-Doppler spectrum of different transmit / receive antenna combinations. Different modes with the same gain in the MIMO radar system are combined. Among the combinations with the same gain, the mode corresponding to the largest virtual array aperture in the horizontal and elevation directions under that gain is selected. The angles of these two modes are resolved and matched separately, and then combined to achieve the maximum virtual array aperture resolution. Digital beamforming is used to match the angle information obtained under the maximum aperture virtual array in the horizontal and elevation dimensions. This invention can effectively increase the maximum array aperture in the original modes with the same gain by utilizing the complementary effect between different reconfigurable array modes while using virtual array reconfigurable technology or MIMO technology.

This invention relates to an improved spatially smoothed source angle estimation method and apparatus based on a coprime linear array. The method includes: acquiring a signal from a source under test using an augmented coprime array to obtain a received signal; vectorizing the covariance matrix of the received signal, sorting the resulting vectors according to the element positions of the uniform linear array, and processing them according to a data processing strategy to obtain a virtual signal received by a virtual array; uniformly dividing the virtual array into overlapping virtual subarrays based on a pre-constructed spatial smoothing rule, and calculating the spatial smoothing covariance matrix of the received signals from the virtual subarrays; performing eigenvalue decomposition on the spatial smoothing covariance matrix using a predefined spatial spectrum estimation method to obtain a spatial spectrum function; and performing spectral peak search on the spatial spectrum function to determine the source angle of the source under test. The method provided by this invention improves the array degrees of freedom and the accuracy of source angle estimation by constructing a larger number of virtual array elements.

The invention provides an array element failure fault-tolerant arrival direction estimation method and device based on incomplete tensor reconstruction, and belongs to the technical field of array signal processing. The method comprises the following steps: carrying out array element working state detection on a received signal of an L-shaped sensor array so as to construct three-order incomplete signal tensors of two direction arrays; performing cross-correlation operation on the third-order incomplete signal tensor to obtain an incomplete cross-correlation tensor, performing virtual array expansion processing to obtain a fifth-order incomplete augmented tensor, and reshaping the fifth-order incomplete augmented tensor into a third-order incomplete target tensor; and generating a mask tensor corresponding to the third-order incomplete target tensor, and then constructing and solving an optimization problem to obtain a factor matrix decomposition result so as to extract an estimation result of the direction of arrival. According to the method, the array physical defect problem is converted into a data recovery task, the self-healing capability defined by software is realized, and the robustness and accuracy of DOA estimation in the array element random failure scene are remarkably improved.

The invention discloses an antenna angle measurement method, device and equipment based on a virtual array. When an angle measurement task of a target antenna is executed for the first time, firstly, a moving track of the target antenna can be determined according to an angle measurement requirement, M physical sampling positions are uniformly selected on the track, and three-dimensional coordinates of the M physical sampling positions are recorded; and then the physical sampling positions are equivalent to virtual array antenna array elements, and a virtual array antenna is formed according to track arrangement. Wireless signals of a narrowband signal source are received on the virtual array and converted into a complex signal matrix, DBF angle estimation is carried out on the virtual array antenna in combination with the complex signal matrix, a DOA preliminary estimation angle is obtained, and adjacent sum and difference beams are constructed based on the estimation angle. And an estimation deviation is solved by using adjacent beams, and the preliminarily estimated angle is corrected to obtain a final accurate angle estimation result. The DOA estimation precision can be improved on the premise that the hardware cost and the system complexity are not increased.

The application provides a high-degree-of-freedom DOA estimation method based on a mirror image co-prime array in a pulse noise environment, and relates to the technical field of array signal processing, and comprises the following steps: S1: obtaining an observation signal by relying on non-circular signal characteristics; S2: calculating a pseudo-covariance matrix based on the information of the observation signal and a square-based correlation entropy operator to suppress the pulse noise; S3: vectorizing the pseudo-covariance matrix to obtain a virtual vector, removing redundant rows in the virtual vector, and performing truncation and sorting according to positions corresponding to continuous virtual array elements to obtain a virtual array receiving signal; S4: performing spatial smoothing on the virtual array receiving signal to obtain a full-rank reconstructed covariance matrix; S5: obtaining a noise subspace by performing eigenvalue decomposition on the covariance matrix; and S6: obtaining an accurate DOA estimation value by performing spectral peak searching on the noise subspace by using a MUSIC algorithm. The method has a high degree of freedom, can accurately complete DOA estimation in a pulse noise environment, and has good performance.

The invention discloses a UWB radar angle measurement method and device based on TDM-MIMO, and belongs to the technical field of radar signal processing. The method comprises the following steps: controlling the radar system to work according to a preset time sequence, switching and controlling the connection and working states of at least two bidirectional channels and at least four physical antennas in different time slices through a switch, and performing time-sharing configuration into a transmitting or receiving mode to obtain echo data; wherein the switching time of the radio frequency switch is less than the difference value between the minimum flight time of the signal and the emission duration time, so as to ensure that the switching does not influence normal transceiving. And recombining the data based on the equivalent spatial positions of the physical antennas in different time slices to form a virtual antenna array, and then estimating the direction of arrival. The device comprises a radar chip, an antenna array, a switching network and a control processing unit. According to the invention, through the optimized TDM-MIMO time sequence and strict time sequence constraint, a large-scale virtual array is formed by using a small amount of hardware resources, and high-precision angle measurement is realized with relatively low system complexity.

The application provides a wide-area monitoring and local gathering adaptive acoustic signal monitoring method and system, including the following steps: at least one sound source acquisition device is arranged in a monitoring area, the sound source acquisition device includes a wide-area subarray and a local subarray; the wide-area subarray of each sound source acquisition device is used for acquiring acoustic signals in the monitoring area to obtain a wide-area monitoring result; if the wide-area monitoring result contains an abnormal sound source, a virtual array is constructed to monitor the abnormal sound source to obtain an abnormal monitoring result, and the abnormal monitoring result includes accurate position information, an audio signal and a real-time spectrum diagram of the abnormal sound source. In the scheme, the wide-area subarray continuously monitors at low power consumption, the local subarray is in a default dormant state, and is activated only when an abnormal sound source is found, so that the overall energy consumption of the system is reduced, global waste of computing resources is avoided, the scheme is especially suitable for resource-sensitive scenes such as edge computing, and the continuity of wide-area coverage is ensured.

The invention belongs to the technical field of information and marine science and technology, and discloses a UUV broadside array DOA estimation method based on conjugate enhancement and virtual extension. According to the method, conjugate enhancement processing is carried out on parallel co-prime array receiving signals, augmented statistical matrixes including autocorrelation, conjugate autocorrelation, cross-correlation and conjugate cross-correlation are calculated, and weighted combination is carried out to construct an extended correlation matrix. The method comprises the following steps: constructing a virtual uniform linear array by using the differential common-array characteristic of a co-prime array, designing a redundancy integration matrix to perform redundancy elimination processing on a covariance matrix, obtaining an equivalent signal of a virtual array, and further reconstructing a virtual array covariance matrix with a Toeplitz structure, and finally, high-precision and automatic pairing estimation of the azimuth angle and the pitch angle of the underwater target is realized through a dual-rotation invariant subspace algorithm. According to the method, the array aperture is expanded, the estimation robustness in a low signal-to-noise ratio environment is improved, spectral peak search is not needed, and technical support is provided for UUV underwater target positioning.

The invention discloses a sound source localization simulation method based on a circular ring co-prime array, which comprises the following steps of: firstly, designing the circular ring co-prime array, acquiring a sound source signal through the array, converting the sound source signal into an array signal, solving a covariance matrix of the signal under a physical array, generating a virtual array through the physical array, and calculating a covariance matrix of the virtual array; and performing MUSIC spatial spectrum estimation on the generated virtual array covariance matrix, calculating a spatial spectrum function, and taking an azimuth angle, a pitch angle and a distance corresponding to a spectrum peak value position as sound source position estimation results. It can be seen through simulation that the method can effectively position the single-frequency sound source, good positioning accuracy can be kept, and the feasibility of the method is verified.

The application discloses a vehicle positioning method and device based on a spatial spectrum estimation method, and the method comprises the following steps: receiving positioning signals of vehicles to be positioned by using multiple coprime antenna arrays and obtaining first received signals by considering noise interference; calculating fourth-order cumulant matrices of the first received signals, constructing a virtual matrix, eliminating Gaussian noise, vectorizing the fourth-order cumulant matrices to obtain second received signals, and calculating a position matrix of a virtual array according to positions of antennas in the coprime antenna array; performing spatial smoothing processing on the second received signals corresponding to a uniform linear part of the virtual array to obtain a smoothing matrix; when the number of vehicles to be positioned is unknown, constructing a noise subspace according to the smoothing matrix and a hyperparameter; constructing a spatial spectrum function according to the noise subspace and a direction vector and estimating a wave arrival direction; and determining vehicle positions in combination with position information of the array. The application can simultaneously position multiple vehicles in real time and with high precision under the condition that the number of vehicles is unknown, and can meet actual application requirements.

An MIMO array sparse rapid design method of a fuzzy function generator based on deep learning comprises the following steps: firstly, directly learning a fuzzy function mapping relation corresponding to virtual array configuration and an incident angle by using a deep learning model so as to replace a traditional analysis fuzzy function calculation process depending on a manifold matrix; and then performing efficient performance evaluation on the candidate sparse array based on the fuzzy function generator, and obtaining a sparse array structure meeting the requirements of high resolution and low sidelobe in combination with an optimization strategy. By means of the technology, acceleration of more than 35 times can be achieved on the premise of not explicitly calculating the fuzzy function, the fuzzy function prediction root mean square error (RMSE) lower than 0.1 is kept, and therefore the sparse array design time is greatly shortened. Experiments on a 2T4R K-band MIMO radar prove that the designed array achieves 10 dB sidelobe level in a 100-degree field of view, the angular resolution is improved by about 32.8%, and the effectiveness and engineering application value of the method in high-resolution MIMO sparse array design are proved.

A novel and useful system and method for extending the virtual array of an existing MIMO automotive radar. In one embodiment, the virtual array is extended by adding one or more additional TX or RX antennas to the existing radar thereby improving the resolution in either azimuth or elevation or both. The additional antennas are added via one or more extender printed circuit boards (PCBs) that are connected to the main radar PCB. The one or more extender PCBs include the additional TX or RX antenna arrays and are adapted to be a set fixed distance in orientation from the main PCB in accordance with the desired virtual array. The one or more extender PCBs and main PCB are mounted in housings that are rigidly mechanically connected to each other. The local oscillator (LO) signal generated on the main PCB is fed to the one or more extender PCBs via any suitable signal connection including RF, electrical, or waveguide connections.

The application provides a DOA estimation method based on a hybrid analog-digital array architecture design, which comprises the following steps: a hybrid analog-digital array is arranged at a receiving end architecture; the hybrid analog-digital array adopts a low-complexity HAD array architecture; the hybrid analog-digital array architecture is used to receive an incident signal and model; an initial value of an analog phase shifter network is designed; a difference virtual array of the low-complexity HAD array architecture is calculated; an initial angle estimation value is obtained from the difference virtual array receiving signal by using a classical direction finding algorithm; after the initial angle estimation value is obtained, the phase shifter network weight is redesigned, and then a difference virtual array output signal is obtained; and a DOA estimation result is obtained from the classical direction finding algorithm; the method can effectively avoid the problems of phase ambiguity and beam scanning, can reduce the cost and complexity, and can effectively approach the estimation performance of a full-digital array architecture.

The present invention discloses a system (100) and method (1200) for ultrasound imaging using arbitrary virtual array sources of aperture excitation. The system (100) comprises at least one user device (102), an imaging device (104), a probe module (106), a sample module (108), a communication network (110) and at least one server (112). The user device (102) is configured to accept input data from the user. The imaging device (104) designed to monitor input data from the user interface and control the functioning of the PAUT probe. The probe module (106) triggers multiple transducer elements based on the input data to generate a wave pattern, where the wave propagates into the sample module (108) for non-destructive testing. The received wave is processed by the imaging device (104) to convert the analogue signal to digital before generating and displaying an ultrasound image of the sample.

Provided are methods and systems for Angle of Arrival estimation, which can include receiving radar signals from a MIMO radar array, generating virtual array signals and virtual array element positions based on the radar signals, generating encoded messages and positional encodings, generating decoded messages based on the encoded messages, positional encodings, and a set of learnable queries, mapping the decoded messages to a plurality of estimation outputs, generating a set of object detections based on the estimation outputs, and navigating a vehicle based on the object detections.

The application relates to a kind of MIMO millimeter wave radar two-dimensional super-resolution angle measurement methods using space-time virtual conversion, comprising: using the orthogonality of transmitting signal, MIMO sparse array is carried out MIMO virtual array transformation, obtain space domain virtual array, obtain the received signal data of space domain virtual array, using the independence of received time domain multiple fast shot data, then carry out time domain virtual transformation, obtain space-time virtual array;Under the antenna layout of space domain virtual array, if the received signal data is single fast shot data, then two-dimensional super-resolution angle measurement is realized using orthogonal matching pursuit (OMP) sparse reconstruction method, if the received signal data is a small amount of fast shot data, then two-dimensional super-resolution angle measurement is realized using sparse bayesian learning (SBL) sparse reconstruction method;If the received signal data is multiple fast shot data, under the antenna layout of space-time virtual array, super-resolution angle measurement is realized using OMP method.The method of the application can increase the effective aperture of array, and significantly improve the angle measurement accuracy of pitch and azimuth dimension.

The invention relates to an active multi-base frequency modulation direct wave interference self-adaptive suppression method, which comprises the following steps: step 1, guiding vector calculation frequency focusing, selecting a signal lowest frequency as a focusing frequency, converting physical array element frequency domain data into virtual array element frequency domain data through linear interpolation, and carrying out linear interpolation on the virtual array element frequency domain data; inverse Fourier transform is carried out to obtain time domain echo data; step 2, reconstructing a time-domain steering covariance matrix, constructing the time-domain steering covariance matrix by using the lowest-frequency steering vector driving time-domain echo data, performing characteristic decomposition on the time-domain steering covariance matrix, selecting a large characteristic value not greater than a signal time bandwidth product and a characteristic vector thereof as a signal component, and taking a mean value of other small characteristic values as an interference component; and reconstructing a covariance matrix. Under the condition that the number of array elements of a large-aperture receiving array is far greater than the time-bandwidth product of low-frequency multi-base frequency-modulated direct waves, the interference of the strong direct waves can be effectively suppressed, and the method has a relatively good engineering application value.

The application belongs to the field of underwater target direction estimation, and combines a linear prediction algorithm with an ETAM algorithm of a vector hydrophone array to estimate the direction of an underwater target. Specifically, the application comprises the following steps: 1) constructing a data matrix of a virtual array after synthetic aperture by using the principle of the ETAM algorithm of the vector hydrophone array; 2) performing high-order linear prediction to solve forward and backward linear prediction coefficient vectors of the matrix; 3) extending the virtual array by k elements to the right or to the left; and 4) performing direction estimation on a signal matrix received by the extended virtual array in the previous step by using a conventional beam forming algorithm of the vector hydrophone array to obtain the target angle. The DOA estimation method of the moving platform vector hydrophone array based on the linear prediction and the ETAM algorithm can realize target direction estimation under the condition of lower signal-to-noise ratio and fewer array elements, and improves the target direction estimation precision and resolution of the underwater moving array.

The application discloses a kind of absolute polynomial correlation entropy DOA estimation methods under pulse noise environment, receive signal by nested array structure antenna, according to received signal and absolute polynomial correlation entropy operator APCO calculate corresponding covariance matrix;With vectorization, ordering and redundancy are removed, obtain new virtual uniform linear array received signal;The continuous part of half wavelength between difference virtual array elements is spatially smoothed, and the spatially smoothed covariance matrix is constructed, and then the precise estimation of DOA is obtained by using the MUSIC method.The method uses absolute polynomial correlation entropy operator APCO to suppress pulse noise outliers, constructs APCO matrix, not only without relying on prior knowledge of noise, but also can get rid of the limitation of traditional correlation entropy algorithm, and can realize high-precision DOA estimation in strong pulse noise, low SNR, limited number of snapshots environment.

The application belongs to the technical field of radio direction finding, and discloses a radio direction finding device and method based on combination of virtual array elements and real array elements. The device comprises N antennas averagely distributed on a planar circle and a multichannel receiver, each antenna is composed of M array elements, M is greater than 3, N is greater than 3, and one virtual array element is arranged between every two adjacent array elements in the M array elements. The method can further increase the number and accuracy of detected incoming waves without increasing array elements, and can simultaneously detect more than the number of array elements of incoming waves.

The application discloses a kind of based on the wave direction estimation method of coprime circular array virtual array, by the construction of virtual uniform circular array, the virtual array element that quantity is much more than physical array element can be obtained under the structure of coprime circular array array, effectively break through the limitation of degree of freedom to the quantity of physical array element, can better adapt the complex scene of multiple signal source coexistence, lay foundation for high resolution DOA estimation;For the array flow pattern mismatch problem caused by the inconsistent equivalent radius of each virtual array element in virtual array, a weighted super-complete dictionary is constructed, and a weight factor is introduced to the steering vector corresponding to different virtual array elements in the dictionary matrix, so that the dictionary can accurately match the virtual array flow pattern structure;Combined with the sparse reconstruction of observation data based on compressed sensing theory, high-precision estimation of signal wave direction is realized.The application can obtain higher array degree of freedom under the condition of fewer physical array elements, effectively reduce the modeling error of virtual array, and improve the precision and stability of DOA estimation.

The invention relates to the technical field of millimeter wave imaging, and provides a millimeter wave radial enhancement imaging method and device, and the method comprises the steps: controlling an MIMO millimeter wave radar array to scan a target region, and obtaining original echo data; performing reference-target-free delay phase self-correction by utilizing an array direct coupling signal, and eliminating phase errors between channels; the corrected data are converted into virtual array data, three-dimensional imaging is carried out through a distance accumulation algorithm, and traditional interpolation errors are avoided; and phase information of the target area is further extracted, a real phase is recovered by using a two-dimensional phase unwrapping algorithm, an accurate distance is calculated, and a high-precision radial profile of the target is reconstructed. According to the precise distance inversion method based on a self-correction mechanism of an array direct coupling signal and phase unwrapping, high-precision millimeter wave radial enhanced imaging without external reference is realized, the limitation of the traditional resolution ratio is effectively broken through, and the radial enhanced imaging with high precision, high resolution ratio and no external reference calibration is realized.