New Ideas to Improve the Performance of Frequency Invariant Wideband Antenna Array Beamforming
Nowadays, it is very important to receive high quality wideband signal in the presence of interference and unwanted environmental effects. To achieve this goal, one way is to improve the quality of signal and decrease the undesired phenomena by antenna array beamforming. In this paper, first we investigate the problem of wideband beamforming in frequency domain considering the effect of interference signals. Then, we present a new low-complex efficient idea to jointly decrease the effect of interference signal and increase the Signal to Interference plus Noise Ratio (SINR). Afterwards, another idea is proposed which increases the value of SINR using some changes in the main beampattern generator. Finally, the performance of new proposed method is compared with previous work by simulations in MATLAB software. Simulation results show that the proposed wideband frequency invariant beamforming approach offers faster convergence and higher gain for main signal with respect to previous work.
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