Limited multiuser detection technique using multisub of correlation Factor for DS- CDMA System

This paper presents the novel concept of limited multiuser detection (MUD) for direct sequence code division multiple accesses (DS-CDMA). The concept uses the correlation properties and bit streaming for reduced complexity architecture to meet real time requirement for asynchronous multiuser detection in wireless communication. To mitigate the effect of multiple access interference (MAI), we propose a multiplication and subtraction (multisub) of cross correlation factor with receiving signal at output of matched filter, which is the first stage of parallel interference cancellation (PIC) multistage multiuser detector. Typically, asynchronous multiuser detector uses multishot detection, which involves block based computations and matrix inversions. Hence, multisub correlation based suboptimal scheme have been evaluated to decrease the computational complexity and eliminate the need for matrix inversion. Moreover, such novel scheme can have added advantage to avoiding multishot detection if they start from a matched filter outputs. The result of the paper shows that performance of the limited parallel interference cancellation (PIC) multistage multiuser detector improves in that of other schemes.