SEMI-BLIND MULTI-USER DETECTORS FOR CDMA

摘要

We consider the problem of multi-user detection for CDMA systems where thecodes of some usersare known while others are unknown, semi-blind multi-user detection. Anexample is at the basestation of a cellular communication system with interference from both in-cellusers, with knowncodes, and out-of cell users, with unknown codes. In this paper we develop anumber of semi-blindmulti-user detectors using a subspace approach. One class of detectorsdeveloped has acomputationally efficient structure of a subspace estimation common to allknown users, followed bya simple processing specific to each user. The performance of the detectors iscompared to that ofthe purely blind detector and the non-blind detector, and the semi-blinddetectors are seen to havethe best performance.