60results about How to "Improve RF Stealth Performance" patented technology

The invention discloses an airborne networking radar radiation parameter joint optimization method based on radio frequency stealth, which belongs to the technical field of radar signal processing. For an airborne networking radar system composed of a plurality of airborne radar transmitters and a plurality of airborne receivers, the airborne networking radar radiation parameter joint optimizationmethod is characterized by acquiring a target RCS and a distance from the target RCS to each receiver relative to each radar transmitter, regarding minimization of an airborne networking radar radiofrequency stealth performance characteristic index as a target, regarding target tracking errors, detection performance and radar radiation parameters as constraint conditions, establishing an airborne networking radar radiation parameter optimization model based on radio frequency stealth, performing joint optimization on radiation parameters such as selection, sampling interval, dwell time and transmission power of the radar transmitters, and effectively improving the radio frequency stealth performance of the airborne networking radar system in a target tracking mode by means of the optimalradar radiation parameters obtained by utilizing the model established according to the method under the condition of satisfying certain target tracking precision and target detection performance.

The invention discloses a subcarrier clustering and power joint distribution method for a radar communication integrated system. The method comprises the following steps: determining a target detection and wireless communication model and environment priori knowledge of the radar communication integrated system; respectively constructing a mutual information expression representing target parameter estimation performance and a data transmission rate expression representing communication performance; estimating a performance mutual information threshold [xi]rad and a data transmission rate threshold [xi]com according to preset target parameters, and establishing a subcarrier clustering and power joint distribution model of the radar communication integrated system; solving the subcarrier clustering and power joint distribution model of the radar communication integrated system. The total transmitting power of the radar communication integrated system can be effectively reduced, and theradio frequency stealth performance of the system is effectively improved.

The invention discloses a networking radar power and bandwidth joint optimization allocation method based on radio frequency stealth. The method comprises: determining the composition of a networkingradar system; taking the radar binary selection variable, the radar transmitting power and the signal bandwidth as independent variables, constructing a prediction Bayesian Cramer-Rao lower bound matrix of a target state estimation error, and taking an element corresponding to a target position component on a diagonal line of the prediction Bayesian Cramer-Rao lower bound matrix as a measurement index of target tracking precision; determining a target tracking precision threshold, and establishing a networking radar power and bandwidth joint optimization model based on radio frequency stealth;and solving the optimization model. According to the invention, constraint conditions such as data processing amount of a fusion center, prediction tracking precision of a target at the next moment and radar emission resources are satisfied. By taking minimization of the total transmitting power of the networking radar system as an optimization target, parameters such as radar selection, transmitting power and signal bandwidth in the multi-target tracking process are optimized, and the radio frequency stealth performance of the networking radar system during multi-target tracking is improved.

The invention discloses a multi-target tracking transmission power allocation method for networked radars based on radio frequency stealth. The method comprises the following steps that S1, a predication Bayesian Cramer-Rao lower bound matrix for target state estimation errors with radar binary selection variables and radar transmission power as independent variables is constructed for a networkedradar system; S2, a multi-target tracking transmission power allocation model for the networked radars based on radio frequency stealth is established with predication tracking precision of a targetat the next moment and transmission resources of the networked radars as constraint conditions and the total transmission power of the minimized networked radar system as an optimization target; S3, the multi-target tracking transmission power allocation model for the networked radars is solved. The method improves the radio frequency stealth performance of the networked radar system during multi-target tracking.

The invention discloses an optimal power control method for a radar-communication integrated system based on radio frequency stealth. The radar-communication integrated system comprises M<T> transmitters, a radar receiver and a communication receiver. The method comprises the following steps: S1, characterizing target detection performance; S2, characterizing communication performance; S3, establishing an optimal power control model of the radar-communication integrated system according to a given communication rate threshold r<com>, a false alarm probability threshold delta<FA> and a target detection probability threshold delta<D> to obtain the optimal radar signal transmission power; S4, building a Lagrangian multiplier formula to obtain optimal communication signal transmission power; and S5, adding the optimal radar signal transmission power obtained in the step S3 and the optimal radar signal transmission power obtained in the step S4 to obtain the minimum total transmit power ofthe radar-communication integrated system. The optimal power control method improves the radio frequency stealth performance of the system.

The invention discloses a non-cooperative game-based radar networking power control method and belongs to the radar signal processing technical field. According to the method of the invention, propagation loss between the radars of a system and a target and the radar scattering cross sections of the target relative to each radar are obtained based on prior knowledge; with a certain target detection performance condition satisfied, the transmission power of the radars is minimized, a non-cooperative game-based radar networking power control model is established, and the model is solved through the classic Lagrangian relaxation algorithm; and after iterative calculation is performed, with the target detection performance condition satisfied, a power value represented by a symbol described in the descriptions of the invention which makes the transmission power of the radars minimum is adopted as an optimal solution, and the minimum total transmission power of a radar networking system, which complies with a constraint condition, can be obtained. With the non-cooperative game-based radar networking power control method of the invention adopted, interference between different radars in the radar networking system can be reduced, and the radio frequency stealth performance of the system can be improved with the target detection performance satisfied.

The invention discloses a method for controlling radiation of a radar on the basis of radio frequency stealth in the cooperating process of passive sensors. The adopted method comprises the following steps of: measuring the maneuver characteristic when a target moves by calculating an innovation vector in the tracking process; measuring uncertainty of a state of the target by calculating covariance matrices before and after filtering; and finally, according to the maneuver characteristic when the target moves and the uncertainty of the state, determining a radiation moment of the radar. According to the invention, the radiation moment of the radar is designed in the cooperating process of the passive sensors. According to the invention, when the radar has higher tracking accuracy, radiation times of the radar can be further reduced, and radio frequency stealth performance of the radar can be further improved.

The invention discloses a multi-target joint optimization method for multi-base radar radiation parameters based on radio frequency stealth. The method comprises the steps of determining the components and working parameters of a multi-base radar system; constructing a prediction Bayesian Cramer-Rao lower bound matrix taking a radar binary selection variable, a radar sampling interval, the residence time and the transmitted signal bandwidth as independent variables, and taking the prediction Bayesian Cramer-Rao lower bound matrix as a measurement index of the prediction tracking precision ofa moving target at the next moment; establishing a multi-target joint optimization model for the multi-base radar radiation parameters based on radio frequency stealth; and solving the joint optimization model. According to the method, under the condition that the emission resource constraint of the multi-base radar system at the next moment is satisfied, parameters such as the radar distributionmode, the sampling interval of the radiation radar, the residence time and the transmitted signal bandwidth are subjected to joint optimization design by taking the minimization of the total residencetime of the multi-base radar to all targets and the sum of the prediction tracking precision of all irradiation targets at the next moment as an optimization target, and the radio frequency stealth performance of the multi-base radar system during multi-target tracking is further improved.

The invention discloses a bistatic radar radio frequency stealth waveform optimization design method. The method comprises the following steps that S1, a target detection channel frequency response Hrad[k] and a bistatic channel frequency response Hbis[k] on the kth subcarrier of a bistatic radar system are obtained; S2, a target time delay estimation Cramer-Rao lower bound expression for representing the parameter estimation performance of the bistatic radar system is constructed; S3, according to a preset target time delay, a Cramer-Rao lower bound threshold deltaCRLB and the radar transmitting power upper limit Pmax on the kth subcarrier are estimated, and a bistatic radar radio frequency stealth waveform optimization design models is built; S4, the bistatic radar radio frequency stealth waveform optimization design models is solved. The method meets the requirement of the given target time delay estimation performance, the total transmitting power of the bistatic radar system is effectively controlled, and the radio frequency stealth performance of the bistatic radar system is effectively improved.

The invention discloses a radar communication integrated system robust resource allocation method based on radio frequency stealth. The method comprises the following steps: S1, obtaining a target detection channel frequency response interval Omega rad between a radar communication integrated system and a target and a communication channel frequency response interval Omega com between the radar communication integrated system and a communication user; S2, under the condition that the frequency response of the target detection channel and the frequency response of the communication channel areuncertain, respectively constructing a Cramer-Rao lower bound expression representing the estimation precision of the target time delay parameter and a communication data rate expression representingthe communication service quality; S3, establishing a radar communication integrated system robust resource allocation model based on radio frequency stealth according to the Cramer-Rao lower bound threshold value delta rad and the communication data rate threshold value delta com; and S4, solving the robust resource allocation model of the radar communication integrated system. The radio frequency stealth performance of the system is effectively improved.

The invention discloses an airborne opportunistic array radar target searching algorithm based on search resource management. The airborne opportunistic array radar target searching algorithm comprises the steps of: firstly, discussing important search parameters, determining priority of each subregion according to priori knowledge, determining average power pavi, beam width theta i and beam residence time tdi of an airborne opportunistic array radar in the i-th subregion as optimization parameters, constructing a signal-to-noise ratio Snri, introducing credibility, and calculating beam position digits Ni and search frame periods Tfpi of different threat level regions; secondly, calculating detection probabilities pdi, and establishing a radio frequency stealth constraint planning model under an uncertain condition of a target threat environment by taking the minimized radiation energy and the maximum detection probability as target functions; and finally, solving the model by adoptingan improved genetic algorithm. The optimized radar target searching algorithm is designed by the invention, has good detection performance, and improves the radio frequency stealth performance of theairborne opportunistic array radar.

The invention provides a forming method of a radio frequency stealth transmitting beam based on a four-dimensional antenna array. Only simple timing sequence design is needed to achieve similar multiple input multiple output MIMO and phase controlled MIMO arrays and even better detection performance, a radar is different from a traditional radio frequency stealth radar, and good radio frequency stealth performance can be given to the radar due to pseudo-randomness of timing sequence. The invention further provides a forming system of the radio frequency stealth transmitting beam based on the four-dimensional antenna array based on the forming method. The forming system has the characteristics of being simple in structure, and easy to realize. According to the forming method and system of the radio frequency stealth transmitting beam based on the four-dimensional antenna array, the generation condition of four-dimensional antenna timing sequence is controlled, under the condition that aradiation signal with good radio frequency stealth performance is ensured, orthogonality among sub-arrays of transmitting antennas or different radio frequency switches is easily realized, a receiving end receives an echo and carries on the signal processing, and information of multiple targets can be simultaneously obtained.

The invention discloses a networking radar multi-target tracking residence time optimization method based on radio frequency stealth. A Bayes Cramer-Rao lower bound of target state estimation errors with radar binary selection variables, radar residence times and emission signal bandwidths as independent variables is constructed and taken as a measurement index of target tracking precision; on this basis, predicted tracking precision, data processing amount of a fusion center and radar emission resources of a target of the next moment are taken as constraint conditions, the total residence time of the minimized networking radar system is taken as an optimization target, and the radar selections, residence times, emission signal bandwidths and other parameters in the multi-target tracking process are subjected to optimization design. In this way, the requirement for the tracking precision of all the targets in the multi-target tracking process is met, the total residence time of the networking radar system is shortened to the greatest extent, and the radio frequency stealth performance of the networking radar system is improved during multi-target tracking is improved.

The invention discloses a radar-communication combined system optimum waveform design method based on radio frequency invisibility. The method includes the following steps that S1, prior information of a target relative to a radar-communication combined system is acquired; S2, the mutual information threshold theta MI and the communication rate threshold Cmin of the performance are estimated according to given target parameters, a mathematical model of waveform A[n] optimization design on an n sub-carrier is established, and an expression of a modulus square of an optimum transmitted waveform on the n sub-carrier of the radar-communication combined system is acquired according to the model. By means of the method, the requirements of target parameter estimation performance and communication rates are met, and the radio frequency invisibility performance of the system is improved.

The invention discloses a networking radar residence time optimization control method based on radio frequency stealth. The method comprises the following steps of (1) an airborne radar network comprises N airborne two-coordinate phased array radars with synchronous space, time and frequency, Q uniform motion targets in a two-dimensional plane are tracked, and an observation model of the airborneradar network and a motion model of the targets are constructed; (2) a BCRLB of a target state estimation error during uniform motion target tracking is acquired, and a lower bound of a target position estimation mean square error is extracted from the BCRLB to serve as a measurement index of target tracking precision; (3) according to a predicted echo signal-to-noise ratio, the predicted detection probability of the airborne radar network for the tracked targets is calculated; (4) an optimization control model for minimizing airborne radar network residence time is constructed, and on the premise that the predicted tracking precision and the predicted detection probability of all the targets meet constraint conditions, the total residence time of the airborne radar network is minimized; and (5) a two-step decomposition method is adopted to solve the optimization control model.

The invention relates to a multi-target tracking sampling interval control method for networking radars based on radio frequency stealth, and belongs to the technical field of radar signal processing.The method comprises the steps of (1) obtaining an RCS (Radar Cross Section) value of each target relative to different radars and the distance of each target relative to the different radars according to each target radar cross section database and target moving state prior knowledge; (2) constructing a Bayesian Cramer-Rao lower bound with radiation resource parameter variables such as a radar allocation variable and a sampling interval to serve as a measurement index for representing the tracking accuracy of each target; (3) establishing a multi-target tracking sampling interval control model for the networking radars based on the radio frequency stealth according to a preset tracking accuracy threshold C<q>max of a target q; and (4) selecting appropriate radars at each moment to perform tracking on corresponding targets at the maximum sampling interval by adopting the multi-target tracking sampling interval control method for the networking radars based on the radio frequency stealth. The radio frequency stealth performance of a networking radar system in the multi-target tracking process is improved according to the invention.

The invention discloses a frequency hopping radar transmission period design method based on an optical bistable chaotic model. The method is characterized in that taking the maximization of the uncertainty of the frequency hopping period of a radar system as an optimization objective, the optical bistable model in the chaotic theory is utilized to generate a chaotic sequence with the pseudo-random, quasi-noise and non-periodic characteristic changes, and the mapping and normalization processing on the sequence in a radar frequency hopping period space is carried out, so that the self-adaptionoptimization design is carried out on the radar frequency hopping transmission period. The beneficial effects of the invention are that an optical bistable chaotic model is used for carrying out theoptimization design on the radar frequency hopping transmission period, and the frequency hopping period with the pseudo-random, quasi-noise and non-periodic characteristic changes, the maximum uncertainty of the signal parameters of the frequency hopping radar is maximized, and therefore the radio frequency stealth performance of the radar system is improved.

The invention discloses a radiation parameter control method for a networked radar system under multi-target tracking. According to the method, a networked radar system formed by a shared radar transmitter and a plurality of radar receivers adjusts radiation parameters like a sampling interval, residence time, and a radiation power of the shared radar transmitter during the multi-target tracking process adaptively and dynamically under the circumstance that preset conditions of all target tracking precision values, detection performances, and the transmitting resource constraint of the networked radar system are met and thus the interception probability of the networked radar system is minimized, so that the radio-frequency stealth performance of the networked radar system in multi-targettracking is improved.

The invention discloses a subcarrier allocation and waveform combined optimization design method of a radar communication integral system. The method comprises the following steps of Step 1, aiming atthe radar communication integral system, according to priori knowledge, obtaining the target detection channel frequency response H<rad>[k] and the communication channel frequency response H<com>[k]on the k-th subcarrier; Step 2, respectively building a mutual information expression representing the target parameter estimation performance and a data transmission speed expression representing thecommunication performance; Step 3, according to a preset target parameter estimation performance mutual information threshold value T<rad> and a preset data transmission speed threshold T<com>, building a subcarrier allocation and waveform combined optimization design model of the radar communication integral system; and Step 4, solving the subcarrier allocation and waveform combined optimizationdesign model of the radar communication integral system. The subcarrier allocation and waveform combined optimization design method of the radar communication integral system has the advantage that the radio frequency stealth performance of the system can be effectively improved.

The invention, which relates to the field of radar signal processing, discloses a Nash-bargaining-solution-based networked radar power allocation method in a spectrum coexistence environment. The method comprises: determining channel propagation losses between all radars and a target in a networked radar system and channel propagation losses between all radars and a communication system as prioriinformation; determining a target detection SINR threshold and a communication system maximum tolerant interference power threshold; establishing a Nash-bargaining-solution-based networked radar powerallocation model in a spectrum coexistence environment; and calculating the networked radar power allocation model to obtain allocation results, and selecting an optimal solution enabling transmitting powers of all radars to be minimized from the allocation results. According to the invention, the radio frequency stealth performance of the networked radar power distribution network radar system can be optimized and the high transmission power of the networked radar is kept to be within the maximum tolerable interference power of the communication system, so that the interference on the communication system by the networked radar is eliminated.

The invention discloses an airborne radar transmitted waveform selection method based on radio frequency stealth. The method comprises the following steps that S1, mutual information I(X1; Xk) betweena signal vector X1 received at the current moment and a signal vector Xk received at the k moment of an airborne radar are adopted to serve as radar target tracking property indexes; S2, KL distancebetween a joint probability density function of a airborne radar emission signal and an intercept receiver receiving signal and a probability density function product of the airborne radar emission signal and intercept receiver background noise is adopted to serve as a comprehensive property index to measure intercept receiver intercepting property and identifying property; S3, an airborne radar transmitted waveform selection model based on the radio frequency stealth is built according to a preset mutual information threshold Ith for representing the target tracking property; and S4, a wholewaveform self adaption selection process is completed according to the airborne radar transmitted waveform selection model based on the radio frequency stealth. The method provided by the invention improves the radio frequency stealth property of the airborne radar.

The invention discloses a radio frequency stealth datalink emitting state acquiring method based on maximum conditional entropy. A prior environmental threat factor x and a prior datalink emitting state y in historic radio frequency stealth data serve as sample spaces. Firstly, the probability density function of the sample space x, the joint probability density function of the sample space x and the sample space y and the characteristic functions of the sample space x and the sample space y are respectively worked out; secondly, a maximum conditional entropy distribution function expression is worked out by building a Lagrange function; thirdly, unknown coefficients in the maximum conditional entropy distribution function expression are worked out, and a maximum conditional entropy distribution function is acquired; fourthly, environment thread factors acquired by situation awareness equipment are input into the maximum conditional entropy distribution function, and a datalink emitting state with the largest uncertainty is acquired.

The invention discloses a distributed MIMO radar transmitting signal optimization design method based on radio frequency stealth. The method comprises the steps of acquiring a reflection matrix H of atarget relative to a radar system, a reflection matrix C of an environment clutter relative to the radar system, and a colored noise matrix N at a radar receiver; establishing a distributed MIMO radar signal optimization design model based on radio frequency stealth; determining an optimal lagrangian multiplier (img file = 'DDA 0001474167540000011.TIF 'wi='67 'he='55'), substituting the (img file= 'DDA 0001474167540000012.TIF 'wi='45 'he='56') into the KKT necessary condition to obtain an optimal emission signal (img file = 'DDA 0001474167540000013.TIF 'wi='158 'he='79') of a distributed MIMO radar, and obtaining a distributed MIMO radar transmitting signal with the radio frequency stealth performance. According to the distributed MIMO radar transmitting signal optimization design methodbased on radio frequency stealth, the total transmitting power of the distributed MIMO radar system is reduced from the practical aspect. Meanwhile, the radio frequency stealth performance of the distributed MIMO radar system is improved.

The invention discloses multi-target tracking time resource and signal bandwidth united optimization method of networking radar. The tracking accuracy of each target in the multi-target tracking process is met, self-adaptive dynamic optimization is performed on parameters such as irradiation target selection, radar allocation mode and emission signal bandwidth during the multi-target tracking process, the target irradiation frequency of a networking radar system during the whole tracking process is reduced to the greatest extent, so that the radio frequency stealth performance of the networking radar system during multi-target tracking is effectively improved.

The invention discloses a radio frequency stealth performance optimization method for a radar and communication combined system. The method comprises the following steps: acquiring target detection channel frequency response and communication channel frequency response prior information; respectively constructing a mutual information expression representing target parameter estimation performanceand a data transmission rate expression representing communication performance; constructing a radio frequency stealth optimization model of the radar and communication joint system; and solving the radio frequency stealth optimization model of the radar and communication combined system to obtain an optimal radar transmitting waveform and optimal communication transmitting power distribution. According to the method, under the condition of considering predetermined mutual information threshold parameter estimation and certain communication data rate delivery information, the total transmitting power of the radar and communication joint system is minimized by optimizing radar transmitting waveform design and communication transmitting power distribution, so the radio frequency stealth performance of the system is improved.

The invention discloses a radar communication integrated networking system power control method based on a non-cooperative game. The method comprises the following steps: determining radar communication integrated networking system composition and propagation loss prior information of each path; respectively constructing a utility function of each radar communication integrated node related to target detection and communication data transmission; respectively establishing a non-cooperative game power control model about target detection and a non-cooperative game power control model about communication data transmission; and solving the non-cooperative game power control model about target detection and the non-cooperative game power control model about communication data transmission. According to the method, the transmitting power of the radar communication integrated networking system is effectively reduced, and the purpose of improving the radio frequency stealth performance of thesystem is achieved.

The invention discloses a multi-base radar transmitting parameter optimization method for radio frequency stealth and target tracking. The method comprises the following steps of: S1, determining a multi-base radar target tracking scene; S2, determining a performance index representing multi-base radar radio frequency stealth; S3, determining a performance index representing multi-base radar target tracking; S4, establishing a multi-base radar transmitting parameter optimization mathematical model for radio frequency stealth and target tracking; and S5, solving the multi-base radar transmitting parameter optimization mathematical model for radio frequency stealth and target tracking. According to the method, the radio frequency stealth performance and the target tracking performance of themulti-base radar in the tracking process are optimized at the same time, the interception probability of an enemy passive detection system on multi-base radar transmitting signals is reduced, the radio frequency stealth performance of the multi-base radar is improved, and the target tracking precision is improved.

The invention discloses a radiation power optimization design method for an airborne radar communication integrated system, and the method comprises the steps: S1, determining the airborne radar communication integrated system, and enabling the system to transmit a plurality of beams at the same time to complete the target tracking and communication data transmission functions; S2, constructing adistance tracking error and angle tracking error expression representing the target tracking performance of the airborne radar communication integrated system, and constructing a data transmission rate expression representing the communication performance of the airborne radar communication integrated system; S3, establishing a radiation power optimization design model of the airborne radar communication integrated system; and S4, solving the radiation power optimization design model of the airborne radar communication integrated system established in the step S3. According to the method, theradio frequency radiation resource consumption of the airborne radar communication integrated system is reduced, and the radio frequency stealth performance of the airborne radar communication integrated system is effectively improved.

The invention discloses a radio frequency radiation control method for a frequency-controlled array MIMO radar communication integrated system. The method comprises the following steps: determining system composition and target prior knowledge of a frequency-controlled array MIMO radar communication integrated system; constructing cramer-Rao lower bound expressions representing target azimuth parameter estimation performance and target distance parameter estimation performance of the frequency-controlled array MIMO radar communication integrated system respectively; establishing a radio frequency radiation control optimization model of the frequency control array MIMO radar communication integrated system; and solving the radio frequency radiation control optimization model of the frequency control array MIMO radar communication integrated system. According to the method, the radio frequency radiation power of the frequency control array MIMO radar communication integrated system is reduced, and the radio frequency stealth performance of the frequency control array MIMO radar communication integrated system is effectively improved.