Recently, multiuser detection has been investigated as an interesting topic because of its capability of eliminating multiuser interference and resistance to the near-far problem. In this paper, we consider a quasi maximum likelihood detector in the reverse link system which used antenna arrays in quasi-synchronous channels. It is also shown that the proposed system can suppress the interuser interference without using the side information of the other users. It is also shown that the performance of the proposed system is superior to that of the conventional matched filter system.