Research On Passive Detection Of Low-slow And Small Targets Based On External Radiation Sources

The paper used LTE signals as external radiation sources to conduct research on the key technologies of ground passive detection systems used to detect LSS-Target(the Low altitude,Slow speed Small Target),mainly focused on passive detection of single targets,multiple target detection,direct wave and multipath clutter interference suppression methods,and source positioning methods were analyzed and researched in three aspects.The main research contents can be summarized as follows:(1)Analyzed the characteristics and ambiguity of the LTE signal,and explained its advantages over other commonly used external radiation source signals;established a ground-based passive detection model based on LTE to calculate relevant parameters based on the detection model,and analyzed maximum detectable distance;the two-station RCS of a typical LSS-Target was simulated with Cad FEKO.(2)Aiming at the characteristics of LSS-Target with weak echo energy,when strong and weak targets coexist,the traditional cross-fuzzy correlation processing method cannot detect weak targets,resulting in missed detection.Aiming at this problem,the method of target detection based on compressive sensing was studied.By modeling and analysing,simulation results showed that the method of target detection based on compressive sensing could detect and distinguish strong and weak targets.(3)Aiming at the problem that direct wave and multipath clutter interference affect target detection,four kinds of clutter suppression algorithms commonly used in passive detection systems were studied.The performance of clutter suppression was compared,and the effects of clutter suppression were analyzed.As a result,simulation results showed that the ECA-B algorithm can suppress clutter interference.(4)For the passive positioning of the target,the TDOA positioning method for three-issue and single-reception and the DOA-TDOA positioning method for single-and-single-reception were studied.The positioning accuracy GDOP of the two positioning methods was simulated and compared.The TDOA positioning method for three-send-one-receive structure can obtain higher positioning accuracy.