Abstract:In order to find out the reason of radar plot missing and track Interrupt-oriented during radar coverage test for low altitude target, aimming at performance index and technical feature of under proof radar, technical parameters which have effect on radar low altitude detection performance were measured. Result show that radar works properly. According to radar actual enviromental conditions, the reason of radar coverage decline was initially mapped on sea surface multipath effect. Based on the model establishing of low altitude multipath echo waveform, the effect on radar detecting coverage of beam splitting caused by multipath effect echo synthesis strength was analyzed, to validate conclusions, radar vertical coverage pattern in the conditon of multipath effect was simulated, comparsion and anlysis testified that the distance of radar plot missing and track Interrupt-oriented conform very closely to simulation result. The analysis result is of great significant to radar design and range trial.