The impact of multipath effect on jamming of active decoy outboard

摘要

Multipath effect of sea surface has an impact on jamming of active decoy outboard. Firstly, the model of multipath effect of sea surface has been determined. Study of multipath effect is based on the simplest model of mirror reflection, in which it is assumed that mirror target is just below real target and that flat ground surface achieves good electrical conductivity. In the case of mirror reflection, it can be solved by studying the relation with reflection of flat ground surface. Secondly, CCIR mathematical model of active jamming under multipath effect has been presented. Plural permittivity of electromagnetism characteristic and reflection characteristic over the ocean are researched. Varying rule of the seawater relative Permittivity, the sea water conductivity, reflection coefficient over slick offing and modified factor over crude offing are analyzed through stimulation. Sea state is used as wave height partitioning adopted by Douglas. Main factor that influence their change is gained. Lastly, impact of multipath effect on active decoy jamming under typical conditions has been analyzed by simulation. It is pointed out that under high level of sea state when roughness of sea surface increases multipath effect will decrease, while under low level of sea state when roughness of sea surface decreases multipath effect will increase. Also when height of active decoy jamming outboard increases energy fluctuation of jamming signal will decrease.