Performance of PIC, SIC and decorrelating detectors for MUD technique in WCDMA system

The wideband code division multiple access (WCDMA) has been selected as the main air interface standard used to meet the high capacity and high bandwidth requirements of the third generation mobile system. The main problem of this technology is multiple access interference (MAI). Various multiuser detection (MUD) methods have been proposed to mitigate this problem. By using multiuser detection (MUD) based interference suppression or cancellation where code and timing (amplitude and phase) information about multiple users are used jointly to detect each individual user more intelligently, system capacity can be significantly improved and possibly less channel coding is needed (Prasad, R et al. 2000). In the search for suitable MUD solutions most emphasis has been placed on the performance and complexity of narrow band CDMA. The question of performance and complexity of MUD techniques under WCDMA system has not been fully explored. In this paper, the performance of MUD under WCDMA system has been evaluated. In the receiver, multistage successive interference cancellation (SIC), multistage parallel interference cancellation (PIC) and decorrelating detector are used to eliminate MAI.