The orthogonal frequency-division multiplexing (OFDM) technique is well known to be robust against the frequency-selective fading in wireless channels. It is due to the exploitation of a guard interval that is inserted at beginning of each OFDM symbol. Based on the conventional OFDM and a polyphase filtered orthogonal frequency division multiplexing (PF-OFDM) technique, we developed an adaptive beamforming algorithm for antenna arrays. The proposed algorithm would lead to an efficient use of channel, since it is possible to eliminate a guard interval and also easily suppress interchannel interference at the same time. In this paper, a series of computer simulations have been provided to show the performance of the proposed system.