A STAP interference suppression technology based on subspace projection for BeiDou signal
Lin Hui Zhao, Ying Mao, Jicheng Ding · 2016
Spatial-temporal adaptive processing (STAP) method can suppress more interferences than the pure spatial filter which has no resolution in frequency. Subspace orthogonal projection technology can remove the interference when the subspace of interference is obtained. Based on the characters of BeiDou signal, noise and jammers, this paper presents a BeiDou interference suppression technique combining subspace orthogonal projection with spatial-temporal processing, which can suppress interferences in different arriving angle and different frequency. Simulation and test results demonstrate that the interference which has the same arriving angle but different frequency with signal can be suppressed in the time domain and the interference which has the same frequency but different arriving angle with signal can be suppressed in the space domain. It is easily to find that the number of time delay has important impact on the performance. When the number of time delay is less than that of the interference frequency, the gain of beam is not the biggest in the desired signal direction and frequency although the nulls are formed in the interference direction and frequency. Otherwise, the gain of the desired signal is the biggest while the interferences are suppressed correctly. With enough array element and time delay unit, the performance of simulation indicates that this method is effective and efficient to multi narrowband interference.