Performance Analysis, improvement and complexity reduction in Multi stage Multi-User Detector with parallel interference cancellation for DS-CDMA System Using odd kasami sequence

Direct Sequence Code Division Multiple Access (DS-CDMA) system is well known wireless technology. This system suffers from MAI (Multiple Access Interference) caused by Direct Sequence users. Multi-User Detection schemes were introduced to detect the users’ data in presence of MAI. In Multi stage Partial parallel interference cancellation (MP-PIC) method complexity is more than multi stage conventional PIC (MC-PIC), but performance is better than MCPIC. In This paper we proposed multi stage subtractive PIC (MS-PIC). In this method the complexity is less than MP-PIC and performance is slightly less than MP-PIC. Now we proposed one more method that is the combination of partial and subtracting parallel interference cancellation (PS-PIC) in multi stage. This method gives to achieve performance improvement and complexity reduction compared to conventional multistage PIC detector. Keywords— Multi-user detection, MAI, Matched filter, , DS-CDMA, PIC.odd kasami sequence.