Performance Investigation of Robust Cylindrical Antenna Array Beamformer in Appearance of Look Direction Mismatch

In this paper, we present a Cylindrical Antenna Array (CAA) and its performance in appearance of look direction mismatch using fixed diagonal loading (FDL) technique. At first, we have compared the performance of CAA with existing concentric circular antenna array (CCAA) to ratify the excellence of CAA beamformer. Then, optimal CAA is compared with delay-and-sum CAA to show the interference rejection capability in appearance of interference signal. The performance of optimal CAA degrades when there exists disparity between beam steering direction and desired signal incoming direction. This performance degradation problem is mitigated by using FDL technique. From the simulation result using MATLAB, it is seen that the half power beamwidth of CAA is 38% better than CCAA and its directivity is higher than CCAA. The power level of side lobes is reduced in CAA and the robust CAA also provides better performance than CCAA in appearance of look direction mismatch.