Direct sequence, code-division multiple access (CDMA) schemes offer an attractive alternative for sharing a transmission medium among many users, while requiring minimal co-operation among them. A number of signal processing issues are related to the receiver's task of multiuser information extraction and detection. In this paper, a discrete-time multirate formulation is introduced for asynchronous CDMA systems, which can incorporate multipath effects. In this framework, linear receivers are derived which can completely suppress multiuser interference (decorrelating receivers). A criterion is introduced, which guarantees the decorrelating property, while providing optimal solutions in the presence of noise. The synchronization problem in a multipath environment is also studied, and identifiability conditions are established. A subspace algorithm is proposed, to estimate the user's delays and multipath channels in a blind scenario.
|Original language||English (US)|
|Number of pages||4|
|Journal||ICASSP, IEEE International Conference on Acoustics, Speech and Signal Processing - Proceedings|
|State||Published - 1995|
|Event||Proceedings of the 1995 20th International Conference on Acoustics, Speech, and Signal Processing. Part 2 (of 5) - Detroit, MI, USA|
Duration: May 9 1995 → May 12 1995