A Comparative Study on pre-FFT and post-FFT Frequency Domain Adaptive Antenna Array for A Broadband Single-carrier multiple access system

In our previous study, we proposed a post FFT frequency domain adaptive antenna array (FD-AAA) algorithm for the uplink detection in the broadband single-carrier multiple access system. In the post-FFT algorithm, the AAA weights on different frequencies are calculated respectively. In this study, we will compare the performance of the proposed algorithm with the pre-FFT type algorithm where the AAA weight vector is calculated before the FFT and all the frequencies share the unique AAA weight. The effects of the distribution of direction of arrival (DOA) spread and three typical DOA models, namely, no spread distribution, uniform distribution and Gaussian distribution will be considered.