Adaptive wide null steering for digital beamforming array with the complex coded genetic algorithm

This paper presents adaptive wide null steering for a digital beamforming (DBF) array with the versatile and powerful genetic algorithm. In this approach, the complex weights of a DBF array are directly coded as the chromosomes for the GA. The GA is able to precisely suppress the sidelobe level, using multiple deep nulls-collectively termed as a wide null-to cover a stretch of azimuth directions. Depending on the prescribed depth of the desired suppression, its proximity to the main beam and the width of the wide null, the original sidelobe level (SLL) of the beam pattern can be maintained. More importantly, this GA approach is applicable for arrays of any configuration, as shown by the numerical results.