Research On Positioning Method For Moving Target Based On Integrated Waveform

With the improvement of modern technology,the living condition of monostatic radar is going from bad to worse,because of the development of anti-radiation missiles and radiation source positioning technology.However,at the meanwhile,the techniques used in high orbit satellite and passive radar are improving rapidly.Compared to original radars,these platforms have better survival abilities.So if we use a high orbit satellite as a emitter,illuminating an interested area on earth,and use passive radars on ground to receive the echo waveforms reflected by the targets,we can significantly decrease the possibility of defensive systems being destroyed by the enemy.And if we use the integrated waveform of radar and communication as the signal,then it's possible to surveille and communicate to the ground at the same time.Based on this background,the paper focuses on the research of integrated waveform LFM-MSK and its feasibility to use in this surveillance and communication system.The paper is constituted of three main parts.Firstly,we do some basic analysis about the integrated waveform,for instance,the formula of LFM-MSK,the modulation and demodulation method,the relationship between error bit rate and signal noise rate,and the radar performance of the waveform through analysis of the ambiguity function.Secondly,we proposed a new processing method,self-multiplication method,based on coherent integration,considering the condition that a passive radar cannot construct matched filter without knowing the information on the integrated waveform.Using this method,we can estimate the range and velocity without knowing the information carried on the waveform,the resolution of the processing result is favorable.Then we analyze and deduce the influences of the cross-term created by the method,and verify that using simulation results.After that,we simulate and analyze the time accuracy and the relationship between detection probability and signal noise ratio.Third,the paper introduces the positioning simulation system built based on the surveillance system mentioned in the first paragraph,telling the methods and theories used in it,such as link analyses,position and velocity estimation and so on.The research results prove that the LFM-MSK waveform theoretically has the sane communication ability as MSK waveform and same radar ability as chirp signal of the same parameters.The range and velocity information can be easily estimated using selfmultiplication method when the symbol of the codes are generated randomly,and the waveform can be used in the situation of long-distance transmission.The simulation system built also proves that the positioning ability of the waveform is favorable.