Vigorous Study on Pre-FFT Smart Antennas in OFDM

Structures of two time domain smart antennas which are combined with OFDM system have been analyzed, namely, simple Pre-FFT smart antenna and a newly proposed channel estimator assisted Pre-FFT smart antenna. Based on the two algorithms, computer simulations have been carried. It is shown in simulation that the channel estimator assisted Pre-FFT smart antenna outperforms the simple Pre-FFT smart antenna at the expense of computational complexities. Simulation also shows that under a severe multipath fading scenario the two Pre-FFT smart antenna algorithms succeed to recover the OFDM system´s immunity to multipath which without them would have been lost.