Research Of Adaptive Sidelobe Cancellation Algorithms For Array Antenna

The adaptive sidelobe cancellation is an effective measure to restrain active jamming. The fundamental theory of ASLC is well studied and a lot of literatures on ASLC performance evaluation under ideal conditions is available. However, there are many issues need to be further studied when implementing the ASLC algorithm to real radar systems. This paper puts emphasis on the research of adaptive sidelobe cancellation technology combining closely with the large circular array atenna.First, this paper discusses the research background of SLC, the basic theory. Then this paper discusses the array antenna pattern synthesis, achieves the low sidelobe antenna pattern using Taylor and Bayliss functions, and the method of null steering. Third, this paper analyses some kinds of factors that effct the adaptive sidelobe cancellation. Cancellation gain of antenna decreases rapidly with increasing of bandwidth of interference, the use of adding elements, adding the tapped delaylines behind the elements are considered as some effective methods of improving the performance. The difference of amplitude and phase between channels influents the performance of adaptive sidelobe cancellation, it can be improved by adding the tapped delaylines behind the elements. This paper also discusses some factors, such as limited learning samples, signal envelop delays and the number of tapped delay lines and so on. This paper also analyses the problem of sidelobe elevation in the process of sidelobe cancellation, and two improved methods are proposed. Simulation results are also given respectfully.