Multiuser Detection in DSSS Systems

Download or read book Multiuser Detection in DSSS Systems written by Shahzadi Mahnoor and published by LAP Lambert Academic Publishing. This book was released on 2014-05-28 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt: Direct sequence code division multiple access (DS-CDMA) is a popular wireless technology in DS-CDMA communications, all of the users' signal overlap in time and frequency and cause mutual interference. The capacity of Direct Sequence Code Division Multiple Access (DS-CDMA) is limited by Multiple Access Interference (MAI) instead of thermal noise. Commercial CDMA systems such as the ones based on IS-95 standard regard MAI as additive noise and employ matched filter detectors. This technique limits the number of users that can be supported in DS-CDMA system to less than 10% of the spreading gain. Moreover the bit error rates for individual users degrade rapidly with an increase in number of users. The conventional DS-CDMA detector follows single user detection strategy in which each user is detected separately without regard for the other users. A better strategy is multi-user detection, where information about multiple users is used to improve detection of each individual user. A number of important multiuser detectors have been proposed here. The content of the book is in following sequence.