Study On Very Long Baseline Of Passive Localization For Bistatic Radar

As a special kind of bistatic radar,passive bistatic radar(PBR)works with bistatic configuration and silent receiving pattern by utilizing external illuminator.Because of these characteristics,PBR has advantages over conventional radars.It works with no electromagnetic pollution,PBR can be deployed in urban area populated regions.Thus PBR has bright value in civil and military application.Traditional PBR exploits target by using frequency modulation broadcast station,television station and cellular phone which are widely distributed on the ground.With the development of the satellite technology,satellitebased PBR obtains wide attention with its wide coverage area and working bandwidth.Because the satellite is rich in resources,multi-transmitting and multi-receiving model has better performance in detection over the single-transmitting and single-receiving model.But owing to the very long baseline between the satellite and the receiver on the ground,the target echoes are very weak which result in the split of Cassini oval.When the conventional localization method is applied over this scenario,the precision of localization degrades obviously and even invalid.Therefore,the paper studies the localization method over satellite based on PBR with very long baseline.In addition,the precision of different target localization method and the configuration of PBR is also analyzed by applying the geometrical dilution of precision(GDOP).Firstly,the paper provides an overview of the development of bistatic radar especially PBR,and the difficulty in localization based on very long baseline are also discussed.Then,the localization principle of direction of arrival(DOA),time difference of arrival(TOA)and frequency difference of arrival(FDOA)is introduced.Meanwhile,the factors which affect the precision of measurements parameter are pointed out.Next,the GDOP in single measurements parameter of the target relative coordinate errors are formulated and obtained.The influence of the target localization method,the mode of localization and the configuration of PBR is analyzed and estimated by simulation.Finally,to overcome the limitation of using single measurement the error equation of target localization based on multi measurements parameter is also deduced and solved.The GDOP of each joint localization method is simulated.Comparing in different simulation condition,the localization method and the mode of localization which suit for very long baseline in PBR are found out.