Research On Technology Of Detection And Tracking For Interception Of Terminal Sensitive Submunition

The terminal-sensitive submunition is a kind of smart antitank ammunition with high efficiency,and it is hard to detect and defend when they are used to attack the panzer group.Due to the greater load capacity and higher flight speed of LMLRS(Long range Multiple Launch Rocket System),how to intercept the terminal-sensitive submunition of LMLRS effectively has been a realistic and challenging topic with a pressing military demand.According to the delivery process of projectile of LMLRS,a research on the interception tactics to terminal-sensitive submunition is carried out.The tactics,that the terminal-sensitive submunition of LMLRS could be intercepted by antiaircraft gun during the flight process of projectile cartridge and the separation process of submunition,is proposed.Based on the process of antiaircraft gun burst firing at the submunition during the different delivery periods,the simulation statistics model is established,and the result proves the feasibility of tactics,meanwhile one of the key prerequisites for success of interception that is the detection and tracking of multiple unresolved targets with monopulse radar is proposed.In order to comprehend the detection algorithm better,the principles of monopulse radar's angle measurement is introduced and the model of radar cross section appropriate to terminal-sensitive submunition is selected,after then,the in-phase and quadrature signals of the outputs of receivers in the sum and difference returns,and the in-phase and quadrature monopulse ratios,are deduced individually.Based on these signal models,the simulation of the response of monopulse radar is given to show that normal monopulse radar cannot resolve the direction of arrival of unresolved targets correctly.The assumption that the DOAs of other targets are uniformly distributed in the beam is made to get a set of new amplitude-conditioned probability density functions which are used to develop a conditional generalized likelihood ratio test,then an improved Neyman-Pearson algorithm for generalized maximum likelihood detection of the presence of multiple unresolved Rayleigh targets is presented,which could detect three or more unresolved targets.The effectiveness of the algorithm is verified by the computer simulations.A novel algorithm based on interacting multiple models(IMM)and particle filter(PF)is developed for joint detection and tracking of unresolved targets using monopulse radar.Firstly,combining the echoes observation and the proposed signal model of the unresolved targets,the proposed approach directly operates on the monopulse sum and difference returns and uses the particles propagating and evolving in the state space to obtain the conditional state probability density of the unresolved targets and realizes the tracking function.Then,the detection of separation motion from cartridge was treated as the maneuver detection of the target,and two motion models are built according to the change regulation of targets' state.The detection of unresolved targets could be achieved by monitor the change of the probability of model.The performance of the algorithm is illustrated via simulations under different conditions.For the tracking problem with a fixed maximum number of targets,a novel joint probability data association(JPDA)particle filter algorithm is proposed,which introduces particle filter concept into the joint probability data association framework.The hypothesis of validation matrix and the rule of data association in original JPDA algorithm are modified,so that the association matrix including unresolved targets could be constructed and the tracking of unresolved targets could be achieved.As far as performance analysis is concerned,a theoretical Cramer-Rao lower bound(CRLB)is derived and the simulation is established to demonstrate the algorithm's tracking performances with a three unresolved targets scenario.The simulation results show that the tracking of three unresolved targets could be achieved,and the tracking performance of the proposed algorithm should be better when the number of targets is less than the maximum.The paper provides theoretical support and technical support for the interception tactics to terminal-sensitive submunition of LMLRS,and also provides basis for the following study of tank active defense technology.