GNSS Interference and Multipath Suppression Using an Antenna Array

A new beamforming technique to suppress the interference signal and the multipath components for the GNSS applications is proposed. This method consists of two stages. In the first stage, by using the fact that the GNSS signal is well below the noise floor, the subspace method is applied to find the interference subspace. In the second stage after despreading the signal, the interference subspace is used as a constraint in the optimization problem. Due to the correlation between the LOS signal and the multipath components, applying the conventional beamformers leads to the signal cancelation phenomenon. A decorrelation approach utilizing an array consisting of several doublets is employed to avoid the signal cancelation phenomenon. It is shown that by utilizing the proposed method the multipath components and the narrowband interference signals can be effectively removed. Several simulation and practical results are provided to demonstrate the effectiveness of the proposed algorithm.