Anti-jamming algorithm for GNSS receivers with array antenna in high speed environment.

When global navigation satellite system (GNSS) receivers move at a high speed, the directions of arrival (DOAs) corresponding to interferences may change rapidly, which will cause a performance degradation of array antenna. A null widening algorithm based on the interference-plus-noise covariance (INC) matrix reconstruction is proposed. Firstly, the number of interferences is estimated via the ratio between adjacent eigenvalues of the sample covariance matrix. Then, the interference DO As are estimated roughly using the spatial spectrum estimates and the spatial spectrum estimates around interferences are reset according to the required null width. Finally, the INC matrix can be reconstructed with the reset spatial spectrum estimates, based on which the weight vector is sloved. Simulation results show that the proposed algorithm performs better than the other null widening algorithms in the carrier to noise ratio (C/N_o), by at least 5 dBHz. Meanwhile, the proposed algorithm has a deeper null when the null width keeps the same. [ABSTRACT FROM AUTHOR]