32 results about "Multistatic radar" patented technology

The invention provides a three-dimensional positioning method and system for a satellite-borne multi-base radar system based on weighted linear iteration, and the method comprises the steps: obtaining radar echo data of a plurality of receivers, carrying out the effective detection of a target, and carrying out the searching of a pitch angle and a space taper angle of a target signal through a two-dimensional adaptive filtering technology, obtaining two-dimensional angle estimation information of the target at different bases and different visual angles; constructing a nonlinear equation set according to two-dimensional angle information and slope distance information of the target under different visual angles, and performing first-order Taylor expansion on the nonlinear equation set to obtain a corresponding linear overdetermined equation set; and forming a precision matrix according to the known measurement precision of the radar system, and carrying out normalization operation and iterative solution on the linear overdetermined equation to obtain the three-dimensional coordinate of the target in the earth-centered earth-fixed coordinate system, thereby obtaining the latitude, longitude and height information of the target, and realizing the high-precision three-dimensional positioning of the multi-static radar system.

A method for supporting radar operations may involve providing, from a radar server, one or more transmit beam parameters, over one or more wired or wireless interfaces, to a first wireless communications system Transmission Reception Point (TRP) for configuring a transmit beam for sending a transmit signal from the first wireless communications TRP. The method may further involve providing, from the radar server, one or more receive beam parameters, over one or more wired or wireless interfaces, to a second wireless communications system TRP for configuring a receive beam for receiving, at the second wireless communications system TRP, an echo signal from one or more targets as a reflection of the transmit signal. The first wireless communications system TRP and the second wireless communications system TRP may be part of a wireless communications system.

A wireless communication network performs multi-static radar operations, including operating multiple access points as geographically-diverse radar transmitters that transmit illumination signals, for illumination of a target region, and an example User Equipment (UE) operates as a radar receiver with respect to the multi-static radar transmission. The network may perform multi-static radar operations on demand, for power savings and interference reduction, and UEs may indicate particular radar-sensing needs or capabilities when requesting multi-static radar operation, for consideration by the network when configuring the corresponding illumination-signal transmissions.

The invention belongs to the technical field of radar signal processing and electromagnetic target characteristic analysis, and particularly relates to an extended target scattering modeling method for a broadband multistatic radar system. According to the method, for aircrafts with complex motion characteristics such as unmanned aerial vehicles and missiles, a unified scattering model under various motion types is established, and multi-base geometric modeling, broadband signal expression and coupling modeling of various target motion mechanisms are introduced; accurate simulation and feature extraction of target scattering characteristics under any transmitting-receiving geometric condition are realized, and a basis is provided for subsequent target identification and parameter inversion.

The application discloses a low-resolution radar reflectivity factor refinement method based on a phased array radar, relates to the radio technology field, and comprises the following steps: time alignment is performed on the cleaned phased array radar linear domain reflectivity factor and the cleaned low-resolution radar linear domain reflectivity factor, and simulation is performed based on an interpolation model; space geometry matching is performed on the cleaned phased array radar linear domain reflectivity factor and the cleaned low-resolution radar linear domain reflectivity factor, and simulation is performed on the phased array radar linear domain reflectivity factor dataset based on a multi-base radar detection data conversion model and a coarse beam simulation operator; a residual network model based on a self-attention mechanism is trained and iteratively optimized to obtain an optimized model, the cleaned low-resolution radar linear domain reflectivity factor data are input into the optimized model, and low-resolution radar spatial refined reflectivity factor data are output. The application can improve the authenticity, physical consistency and business availability of the refined reconstruction result.

The invention discloses a multi-static radar system deployment method considering position uncertainty, and relates to the technical field of radar systems. The method comprises the following steps: dividing a monitoring area into distinguishing units; establishing a candidate deployment model of radar nodes on the motion platform; constructing a position deviation area with the ideal position as the center; performing spatial averaging on the signal-to-noise ratio based on the region to obtain an average signal-to-noise ratio of each resolution unit; determining the lowest average signal-to-noise ratio and the effective coverage rate; and solving an optimal deployment scheme by adopting a multi-target optimization algorithm by taking the two as a joint optimization target. According to the invention, the coverage capability and the performance stability of the radar system under node position disturbance can be effectively improved.

The invention provides a dual-multistatic radar system based on an all-optical architecture, which comprises a transmitting station and a receiving station, adopts the all-optical architecture, fully adopts microwave photon technical achievements, and comprises an optical frequency source, optical up / down conversion filtering, an optical phase shift network, optical beam forming, optical channelization and an optical ADC (Analog to Digital Converter). The characteristics of wide working band, low phase noise dispersion, low delay loss and the like of microwave photons are fully utilized; the system adopts a dual multi-base mechanism, supports receiving and transmitting separation and multi-view target observation, and has the system advantages of extremely strong anti-stealth, low interception, anti-interference and the like; the system adopts a wireless synchronization technology based on 1PPS signals to solve the problems of synchronization and signal coherence of the double-base radar and the multi-base radar, the practical scene of the system is effectively widened, and the layout difficulty of the system is reduced.

This invention discloses a target localization method for multiple-transmitter, multiple-receiver passive multistatic radar under interference conditions. The method includes: acquiring reference channel signals and echo signals and performing signal characterization preprocessing to obtain reference channel signal matrices and echo signal matrices; estimating channel parameters based on the reference channel signal matrices and echo signal matrices using the generalized likelihood ratio principle to construct a DPI-GRLT detector; solving the DPI-GRLT detector and calculating the detection statistics at each grid point to obtain the radar target information estimation result. This invention can maintain high localization accuracy and achieve rapid estimation and resolution of multiple targets even under weak signal conditions. As a target localization method for multiple-transmitter, multiple-receiver passive multistatic radar under interference conditions, this invention can be widely applied in the field of radar target localization technology.

An entanglement-assisted multistatic quantum radar detection technique employs the integrated entangled source shared among multiple transmitters and performing transmit side optical phase conjugation. EA receivers are based on classical homodyne detection schemes. The EA multistatic radar detection technique is evaluated against bistatic radar EA detection scheme and various coherent states-based quantum detection schemes (the optimum quantum detector. Helstrom threshold detector, and random phase optimum quantum detector). The EA multistatic target detection probability is significantly better than that of corresponding bistatic radar EA detection techniques. coherent states-based quantum detection techniques. and the classical radar detection schemes. When both scattered signal photon channels and idler channels are noisy and lossy, the scheme significantly outperforms the EA bistatic radar scheme.

From a first perspective, a radio device (R1) is provided, configured for wireless communication and for bistatic or multistatic radar detection, comprising a transceiver, a memory, and a processor coupled to the transceiver and memory. The transceiver and processor are designed to receive a baseband receive signal from a second radio device (R2) via the transceiver. This receive signal includes a coded message and a plurality of reference signals after transmission over a wireless channel (102). The transceiver and processor are designed to calculate channel state information using the plurality of reference signals contained in the baseband receive signal.The transceiver and processor are designed to calculate an estimate of a transmitted signal originally sent by the second radio device using the channel state information and the received signal. The transceiver and processor are designed to perform at least demodulation and channel decoding on the estimated transmitted signal to obtain an estimate of the message transmitted by the second radio device. The transceiver and processor are designed to generate a reconstruction of the transmitted signal by performing baseband signal processing and reference signal insertion on the estimated message, where the baseband signal processing and reference signal insertion correspond to the baseband signal processing and reference signal insertion performed by the second radio device.The transmitter-receiver and the processor are designed to generate sensor channel data by combining the reconstruction of the transmitted signal and the received signal.

The invention provides a construction method of a dual / multistatic radar anti-interference digital simulation platform for offshore / port intelligent comprehensive monitoring scenes. Aiming at the difficulties that functions, interfaces and data streams are complex and the like, the general architecture is decoupled by adopting a resource layer, a function layer and a user layer according to the principles of upgradeability, expandability and easiness in maintenance, networking radar scene simulation configuration, radar configuration design, target and interference echo generation, radar detection imaging and efficiency analysis modules are developed, and an all-digital simulation platform is established. Based on a platform design scenario experiment, aiming at large and medium-sized ship targets from the dimensions of a technical system and a geometric configuration, under the environments of illegal electronic equipment interference, multi-radar mutual interference, ship metal component interference and combined interference, different ship target types, offshore / port scene parameters, interference types and radar configurations are flexibly configured, so that the ship targets can be quickly and accurately positioned. And the module adaptability, expansibility and stability of the platform and the reasonability of core verification architecture design are verified.

The invention discloses a multi-static radar physical target and active false target identification method, and belongs to the field of target identification and interference resistance. The method comprises the following steps: estimating deception parameters of a target in a plurality of coherent processing intervals on the basis of measurement information based on a multi-static radar, so as to combine and form a deception parameter vector; according to the characteristic that physical target deception parameters approximately obey zero mean Gaussian distribution, variance is calculated, and a reference vector is constructed; mapping the deception parameter vector and the reference vector to a matrix manifold or a power spectrum manifold; adopting total Bregman divergence and three types of geometric metrics thereof to define a geometric distance; calculating a geometric distance between the target mapping point and the reference point; and comparing the result with a threshold value to realize the discrimination of the physical target and the false target. According to the method, the separability of physical target and false target distribution is enhanced by utilizing information geometric measurement, and the discrimination performance is remarkably improved; the method can achieve excellent performance under the condition of a small number of samples, adapts to real-time countermeasure requirements, and is high in target recognition robustness and controllable in complexity.

Existing multistatic configurations of Radar systems requires a direct LoS signal and / or time synchronization among the Radar transmitter and the multistatic distributed Radar receivers. The present disclosure provides a phaseless frequency-modulated continuous-wave multistatic Radar (PFMR) imaging that relaxes requirement of the direct LoS signal and only requires a plurality of parameters of a FMCW signal comprising a chirp signal rate, a carrier frequency and, a period of chirp to be known. Further, it also removes condition of the time synchronization among a plurality of FMCW multistatic distributed Radar receivers. However, because of absence of the time synchronization among a plurality of FMCW multistatic distributed Radar receivers, an unknown random phase offset appears after deramping. The present disclosure eliminates the unknown random phase offset, by performing autocorrelation function on a mixed signal, resulting in a phaseless measurement data corresponding to a plurality of FMCW Radar imaging signals.

This disclosure provides systems, methods, and apparatus, including computer programs encoded on a computer storage medium, for multi-static radar communication. In some implementations, a transmitting device may transmit a radar alert frame to a receiving device followed by a codeword and one or more radar pulses. The radar pulses are transmitted in several directions using beamforming. The timing information indicates a timing offset or delay between one or more codewords in the sequence of codewords and the start of the radar pulse. The receiving device may detect one or more codewords in the sequence of codewords and an echo of at least one of the radar pulses and determine a time at which the corresponding pulse is transmitted by the transmitting device. The receiving device may compare the timing of the echo to the timing of the transmitted pulse to determine the relative distance of the object producing the echo.

This invention relates to a method for secure synchronization and authentication of radar data frames for a bistatic or multistatic radar system, comprising the steps of: generating an unpredictable authentication sequence or a key for calculating the unpredictable authentication sequence; synchronizing at least one subsequence of the authentication sequence or the key between components of the radar system via a secure communication channel, wherein, in the case of key synchronization: generating a subsequence of the unpredictable authentication sequence using the key; embedding the subsequence of the authentication sequence into the radar data frame; transmitting the radar data frame through a transmitter of the radar system; receiving the radar data frame through at least one receiver of the radar system; and matching the subsequence of the received radar data frame with the subsequence of the transmitted radar data frame for authentication of the received radar data frame. The invention further includes a radar system capable of implementing the method.

A node in a wireless communication system coordinates multistatic radar measurements, wherein the node controls a plurality of wireless communication devices. Coordination involves obtaining an indication that a first sensing area located within a geographic area that is served by the node is to be sensed by a first radar signal. A first multistatic radar group of wireless communication devices selected from a participating group of the plurality of wireless communication devices and the node is formed, wherein the first multistatic radar group comprises at least one device for transmitting the first radar signal and at least two devices for receiving one or more reflections of the transmitted first radar signal. The first multistatic radar group is controlled to introduce the first radar signal into the first sensing area and to receive the one or more reflections of the introduced first radar signal. The sensed reflections obtained by wireless communication devices in the first multistatic radar group are caused to be combined to obtain geographical information about the first sensing area. Other aspects involve a wireless communication device interacting with a network node to receive allocated time and radio frequency resources to be used for a radar function.

According to a first aspect, there is provided a radio device (R1) configured for wireless communication and bistatic or multistatic radar sensing, comprising a transceiver, a memory, and a processor coupled to the transceiver and the memory. The transceiver and the processor are configured to, after transmission over the wireless channel (102), obtain, via the transceiver, a baseband receive signal comprising an encoded message and a plurality of reference signals from a second radio device (R2). The transceiver and the processor are configured to calculate channel state information using a plurality of reference signals included in the baseband receive signal. The transceiver and the processor are configured to calculate an estimate of a transmitted signal originally transmitted by the second radio device using the channel state information and the received signal. The transceiver and the processor are configured to perform at least demodulation and channel decoding on the estimate of the transmitted signal, thereby obtaining an estimate of the message transmitted by the second radio device. The transceiver and the processor are configured to generate a reconstruction of the transmitted signal by performing baseband signal processing and reference signal insertion on the estimated message, wherein the baseband signal processing and reference signal insertion correspond to the baseband signal processing and reference signal insertion performed by the second radio device. The transceiver and the processor are configured to generate sensed channel data by combining the reconstructed and received signals of the transmitted signal.

This invention discloses a method for accumulating and detecting high-speed maneuvering targets under range-velocity joint deception jamming, applied to the field of radar anti-jamming. It addresses the problem that existing technologies struggle to accurately identify range-velocity joint deception jamming and effectively detect high-speed maneuvering targets in multi-static radar systems under low signal-to-noise ratio conditions. First, this invention constructs an echo model of a high-speed maneuvering target under range-velocity joint deception jamming. Then, it proposes a method based on topological Euclidean distance to achieve multi-channel coherent accumulation and acquire target position estimation information for each channel. Finally, it uses hyperbolic-elliptic joint positioning to process the position estimation information, rapidly obtaining the physical target's position estimate and accurately identifying range-velocity joint decoy targets.

The application provides a kind of based on weighted linear iteration's spaceborne multi-base radar system three-dimensional positioning method and system, comprising: obtaining the radar echo data of multiple receivers and effectively detecting target, search the elevation angle and spatial cone angle of target signal by two-dimensional adaptive filtering technology, obtain the two-dimensional angle estimation information of target under different base different visual angle;According to the two-dimensional angle information and slant range information of target under different visual angle, construct nonlinear equation group, and carry out first-order Taylor expansion to it, obtain corresponding linear overdetermined equation group;According to the measurement accuracy known to radar system, form accuracy matrix to the linear overdetermined equation and carry out normalization operation and iterative calculation, and calculate the three-dimensional coordinates of target in the earth-centered earth-fixed coordinate system, and then obtain the longitude and latitude and height information of target, realize the high-precision three-dimensional positioning of multi-base radar system.

The application discloses an anti-deception jamming method based on networked radars, which comprises the following steps: configuring networked radar systems as virtual isomorphic networking radar mode, virtual multi-base radar mode and virtual active / passive radar mode respectively; obtaining the anti-deception jamming success rate of the virtual isomorphic networking radar mode; obtaining the anti-deception jamming success rate of the virtual multi-base radar mode; obtaining the anti-deception jamming success rate of the virtual active / passive radar mode; selecting the mode corresponding to the maximum value among the anti-deception jamming success rates of the virtual isomorphic networking radar mode, the virtual multi-base radar mode and the virtual active / passive radar mode as the final mode. In the process of establishing the multi-station radar, the application can ensure that radars with multiple functions and systems are deployed at the same time, overcome the shortcomings of the existing single multi-station radar system, and meet different anti-jamming performance requirements.

Various technologies described herein pertain to opportunistically employing passive multistatic radar processing in automotive radar systems. A radar system of an autonomous vehicle is controlled to operate in an active mode during a first time period as the autonomous vehicle travels along a route. A transmitter and receiver of the radar system are enabled in the active mode. The radar system is controlled to operate in a passive mode during a second time period as the autonomous vehicle travels along the route. The transmitter is disabled and receiver is enabled in the passive mode. While in the passive mode, the receiver of the radar system receives a reflected radar signal responsive to a radar signal transmitted by a differing radar system of a differing autonomous vehicle. An object is detected based on the reflected radar signal and transmission information pertaining to the differing radar system of the differing autonomous vehicle.

Existing approaches for estimating delay-doppler values in Information Sharing and Analysis Center (ISAC) with multistatic radar receiver have the disadvantage that they are estimating integer bin shifts and require separate estimation of delay and doppler values, requiring additional step of computationally demanding data association and distinguishing the signal from different transmitter. Embodiments disclosed herein provide a method and system for estimating fractional bin shifts in ISAC with multistatic radar. In this approach, the system estimates paired fractional delay-doppler bin shifts by utilizing the one or more phase information and the dictionary matrix. and computing the cross correlation of the received at least one signal and the associated transmitted signal. Cross correlation utilized for identifying the one or more transmitter with respect to at least one signal transmitted.

The application discloses a kind of multi-platform time correction methods based on dual multi-static radar detection, comprising the following steps: time error correction task initiation, the task is initiated by artificial or automatic method;The multi-node to be corrected time is numbered;Air common view target selection;Air target's fixed data rate dual multi-static detection;Inter-node dual ranging: obtain the Mth dual distance;Equivalent distance fitting;Time error correction.The application can complete multi-platform real-time high-precision time synchronization error correction according to radar detection results, and the process is implemented at the same time of target detection, without occupying additional resources;At the same time, without additional dedicated time comparison module, the integration of platform equipment is improved.

The invention belongs to the technical field of multi-base radar and radar signal processing, and discloses a multi-base positioning method based on distance and distance change rate. According to the method, a weighted least square problem taking a target position as an optimization variable is established through time delay of a direct path and an indirect path collected by a receiver and a Doppler frequency shift measurement value, then the problem is relaxed into a positive semidefinite programming problem by universally applying a positive semidefinite relaxation technology, and then position estimation of a target is solved. The precision of the target position estimated by the method provided by the invention can reach the Cramer-Rao lower bound under the condition of small Gaussian noise; the positive semidefinite relaxation method provided by the invention is superior to a two-step weighted least square method in the prior art, and has more obvious advantages especially under the condition of large noise; according to the method provided by the invention, the positioning precision of the target is greatly improved.

Some examples of the disclosure are directed to implementing a passive and adaptive bistatic or multi-static radar system. Some examples of the disclosure are directed to using reflections from one or more navigational aids. Some examples of the disclosure are directed to generating a digital model of a physical environment to implement a deterministic passive radio system. Some examples of the disclosure are directed to collaborative approaches to identifying, locating, and track airborne objects.

The invention relates to the technical field of radar target tracking, and provides a system error online registration method and system based on multistatic radar target tracking, and the method comprises the steps: estimating the rough position of a target, and carrying out the iterative correction of the precise position and covariance matrix of the target for any transmitting station i based on the observation of the target; estimating a target state, a covariance matrix of the target state, a system error and a covariance matrix of the system error through the accurate positions and the covariance matrixes of the two adjacent moments; updating the state of the target by using the new distance and observation received from the transmitting station at the next k moment; and updating the system error by using new azimuth observation and new pitching observation which are received from the transmitting station at the next k moment. According to the method, the system error is output in real time under the condition that the radar system error changes along with time and no real data reference exists.

The invention discloses a multi-static radar system deployment optimization method in a non-connected deployment area, and belongs to the technical field of radar systems. The method comprises the following steps: dividing a monitoring area into resolution units, and constructing a multi-target model taking an effective coverage rate and a minimum signal-to-noise ratio as optimization targets; decomposing a radar node position variable into a segmented variable and a continuous variable, representing a subordinate sub-region through an integer variable, and converting the segmented variable and the continuous variable into a multi-target mixed integer programming model; and adopting a multi-target particle swarm optimization algorithm to respectively implement differential updating strategies on the continuous variables and the integer variables. According to the method, a complex constraint processing mechanism is not needed, and the Pareto optimal deployment scheme can be efficiently and stably obtained in the non-connected deployment area.

Techniques are disclosed for determining the location of an object by using reconfigurable intelligent surface (RIS) assisted RF sensing. Radar techniques can be used in which one or more base stations act as a transmitter and a receiver device acts as a receiver in a bistatic or multistatic radar configuration, with a RIS directing signals transmitted by the one or more base stations to the receiver device. By comparing the time at which the receiver device receives a line-of-sight (LOS) signal (redirected to the receiver device by the RIS) with the time of an echo signal from a reflection of an RF signal off an object (redirected to the receiver device by the RIS), the location of the object can be determined. Depending on the desired functionality, the location can be determined by the receiver device or by a location server or other network entity.

The invention discloses a GNSS-based space-based multi-static radar time synchronization method and system, relates to the technical field of radar cooperative detection, and aims to solve the problem of large accumulative error caused by long-time operation of a crystal oscillator in an existing radar time synchronization method. The GNSS-based space-based multi-static radar time synchronization method utilizes GNSS (Global Navigation Satellite System) time signals and information to calculate inter-satellite clock skew data; according to the time synchronization method, time delay adjustment is carried out, a timing signal is triggered, time synchronization is established, a local constant-temperature crystal oscillator is locked by using a GNSS standard time signal, frequency calibration is carried out on the constant-temperature crystal oscillator, and time synchronization of the space-based multi-static radar is realized. According to the technical scheme, the long-time stability and accuracy of the crystal oscillator can be effectively improved, and the problem of large accumulative error caused by long-time operation of the crystal oscillator is avoided.

Some examples of the disclosure are directed to implementing a passive and adaptive bistatic or multi-static radar system. Some examples of the disclosure are directed to using reflections from one or more navigational aids. Some examples of the disclosure are directed to generating a digital model of a physical environment to implement a deterministic passive radio system. Some examples of the disclosure are directed to collaborative approaches to identifying, locating, and track airborne objects.