A Kind of Cascade Anti-Jam Method for GPS Receiver

The anti-jam technique of GPS is researched in the paper, a cascade anti-jam method is proposed, and it eliminates narrowband interference (NBI) in transform domain, and suppress the residual interferences with array processing method which utilizing Matrix decomposition.A spectrum slicing method is proposed as the frequency excision algorithm for NBI rejection in transform domain. After NBI elimination, the decomposition of matrix based on improved Jacobi algorithm which reduce computation is discussed. Simulation indicates that when wideband interference exists, narrowband interference can be detected and eliminated using the proposed method. Through simulation, it is tested that in multiple jam environment, the method has a better anti-jam capability then space-time adaptive processing (STAP) anti-jam method.