Design And Implement Of Distributed Digital Broadcasting-based Passive Radar Receiver System

Passive radar is one of the most popular research topics in the field radar for more than 20 years.The core technology of passive radar is mainly led by western countries for a long time.But in recent years,some Chinese universities and research institutes have invested a lot of energy to follow up and made some advanced results as well.There are various kinds of third-party sources for passive radar,including broadcasting and television base stations,satellites,communication base stations,wireless local area networks and so on.Among them,the digital broadcasting(television)based passive radar(DBPR)has its unique advantages,and has been deeply studied by many research institutions.The theory and system design of bistatic passive radar with single transmitter and single receiver is approaching maturity.It is obviously known that distributed and multistatic structure is the development trends for passive radars.Distributed detection can effectively compensate the shortage of uncontrolled transmitters in passive radars,thereby becoming an important approach to improve the detection performance.Most modern digital broadcasting and television systems work on a network,such as DTMB/CMMB/CDR in China,DVB-T/DAB in Europe,which not only provides a natural condition to distributed passive radar but also puts forward higher requirements on the design of passive radar systems.Distributed passive radar system is composed of a number of associated radar receiver system units.So first of all,the reliable receiver system unit should be designed.After that,an important problem of precise synchronization among the receivers and transmitters,which mainly involves frequency and time synchronization,needs to be solved urgently.This paper has studied the characteristics of digital broadcasting(television)signals and passive radar,and designed a set of distributed digital broadcasting-based passive radar(D-DBPR)receiver system.Firstly,it introduces the basic theory of designing passive radar receiver system as well as the detection principle of passive radar.The difficulties in the system design are analyzed and the solutions are given.Then,the system design scheme and the implementation process are in detail described.To satisfy the synchronization requirements of D-DBPR,it firstly analyzed the synchronization requirements of the system.Then,by learning the synchronization principle of the digital broadcasting and television transmission system,a synchronization scheme based on GPS is presented.Moreover,an effective scheme based on the frame structure of CMMB signal is proposed to test the synchronization performance of the system.Finally,the basic performance of the system is tested.And the reliability of the system is verified via the distributed multistatic passive radar experiments.