Subspace-based multiuser detector for DS-CDMA systems over flat fading channels

An adaptive multiuser detector based on signal subspace estimation is proposed for a synchronous DS-CDMA system over flat fading channels. It is shown that under this scheme, the linear MMSE detector can be obtained. Based on the training sequence transmitted by the desired user, the proposed detector does not require knowledge of the code sequence and the propagation channel response of the desired user. The proposed adaptive multiuser detection technique is shown to be computationally efficient and robust against the near-far problem