Error Modeling And Performance Affecting Coherence Of Highly Maneuvering Distributed Coordinated Radar

Compared with the phased array radar,which is expensive,unmaneuverable and easily destroyed,the high maneuvering distributed cooperative coherent radar system consists of multiple mobile small aperture unit radars distributed.By synthesizing the signal level of the echo envelope,received by each unit,the signal-to-noise ratio of targets can be improved,if necessary,the received pulse can be coherently accumulated in the time dimension.The high maneuvering distributed cooperative coherent radar can be equivalent to a large power detection radar,which meets the performance requirements of modern warfare for high precision,anti-stealth and anti-interference.In addition,the high maneuvering distributed cooperative coherent radar also has many advantages,such as high sensitivity,long-distance identification,searching and tracking of the targets,strong maneuverability,and rapid deployment according to the combat environment.At present,there are many results in the theory of distributed coherent cooperative radar technology.However,since the coherence is affected by the actual various system errors,it is urgent to solve the error boundary conditions and error compensation methods under actual scenes,including time synchronization error,frequency synchronization error,antenna phase center error,inertial navigation error,motion error etc.When the errors of the system do not meet the requirements of coherence,how to improve the coherence of the signals is of great significance.In this thesis,the application background,main performance and technical problems of distributed cooperative coherent radar are firstly described.Secondly,the distributed cooperative coherent radar system are modeled for static mode and high maneuvering mode separately.Thirdly,the block diagrams of the processing flow of different types of orthogonal signals in the receiving coherent mode are illustrated,the simulations and performance analysis are given based on the positive and negative chirp signals.Fourthly,the sources of various systematic errors,affecting the coherent performance of highly maneuvering distributed coherent radar system,is analysised,the errors models are given,error compensation scheme and model are given,and all verified by simulation.The boundary requirements of each system error are given under the rated signal-to-noise ratio(SNR)requirement.Fifth,an envelope alignment method based on frequency-domain correlation is proposed for the extended target in the actual scene.In addition,when one or more systematic errors exceed the error boundary requirements,a coherent method to improve the SNR and the target positioning scheme are proposed,which are verified by simulation and field experiment data.The results show that the robust signal coherent accumulation method for high maneuvering radar cooperation proposed in this thesis,not only solves the problem of envelope alignment for extended targets,but also improves the accuracy of envelope alignment.By using the parameters of the goniometer and the beamscan method,the purpose of improving the SNR of the coherent signal is realized.The target location and tracking is realized by the method of target calibration.Finally,the future work of the high maneuvering distributed coherent radar is pointed out.