An improved reduced-rank STAP interference suppression method in design of GNSS receivers

In this paper, we address the problem of interference cancellation in global positioning system (GPS) receiver using an adaptive reduced-rank space-time adaptive processing (STAP) interference suppression method based on multistage nested Wiener filter (MSNWF). This improved adaptive reduced-rank method is based on the improved Gerschgorin radii algorithm. First, the cross-correlations between the desired signals of the adjacent stages of MSNWF are directly used to calculate the Gerschgorin radii instead of employing the eigenvalue decomposition of the covariance matrix. Then, a heuristic decision rule based on Gerschgorin disk estimator (GDE) is employed to estimate the rank of interference subspace. Thus optimal rank can be adaptively selected without increasing the computation. Analysis and results of the experiment show that the proposed method further reduces the computation of STAP and enhances its real-time property with the interference suppression performance unaffected.