Performance Improvement of MAI Cancellation in Fading DS/CDMA Channels

Kilsoo JEONG  Mitsuo YOKOYAMA  Hideyuki UEHARA 

Publication
IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences  Vol.E88-A  No.10  pp.2869-2877
Publication Date: 2005/10/01
Online ISSN: 
Print ISSN: 0916-8508
Type of Manuscript: Special Section PAPER (Special Section on Information Theory and Its Applications)
Category: Communication Theory
Keyword: 
asynchronous DS/CDMA,  single-user strategy,  adaptive receiver,  modified MMSE, 

Full Text: PDF(907.8KB)

Summary: 
In this paper, we propose a single-user strategy for demodulating asynchronous direct-sequence code-division multiple access (DS/CDMA) signals for improving the performance of the adaptive receiver in fast fading channels. Since the adaptive receiver depends on the channel coefficient of all users, it cannot be implemented adaptively in fading channels due to severe tracking problem. A proposed adaptive receiver based on the modified minimum mean-squared-error (MMSE) criterion is used for solving this problem. By simulation, it is verified that our proposal is a promising method to solve the problem, and the results show that the proposed adaptive receiver has substantially larger capacity than the conventional adaptive receiver in fast fading channels.