The conventional matched filter (MF) receiver is considered the optimum filter to recover the CDMA signals. One of the problems of the MF is that its performance is significantly degraded due to the channel impairments and the increase of the multiple access interference (MAI). In this paper, an adaptive minimum mean square error-maximum likelihood (MMSE-ML) receiver is introduced to overcome this problem. This receiver uses two sets of adaptive coefficients to increase the ability of tracking the time variations of the channel. The performance of the receiver is measured in terms of bit error rate (BER) and compared with other receivers over flat fading channel. It is found that the performance of the
adaptive MMSE-ML receiver is much better than the performance of the other receivers in the flat fading channel.