Title :
Novel multiuser interference canceling scheme in the downlink of TDD-CDMA systems
Author :
Wang, Ji-Bing ; Zhao, Ming ; Zhou, Shi-dong ; Yao, Yan
Author_Institution :
Dept. of Electron. Eng., Tsinghua Univ., Beijing, China
Abstract :
In TDD-CDMA systems, the downlink multipath channel parameter can be estimated from the uplink. In this paper, we use the instantaneous channel parameter to calculate the spreading spectrum code and despreading code for different users. We present the optimal criterion of the generation of the spreading code and despreading code, so that the multiple access interference can be greatly decreased. Numerical results show that our scheme can greatly increase the signal to interference and noise ratio, compared with conventional CDMA systems which use a Gold sequence as the spreading code.
Keywords :
code division multiple access; codes; indoor radio; interference suppression; land mobile radio; multipath channels; multiuser channels; parameter estimation; spread spectrum communication; time division multiplexing; TDD-CDMA systems; despreading code; downlink multipath channel parameter; instantaneous channel parameter; multiple access interference; multiuser interference canceling scheme; signal to interference ratio; signal to noise ratio; spreading spectrum code; Base stations; Downlink; Filters; Interference cancellation; Intersymbol interference; Multiaccess communication; Multipath channels; Multiple access interference; Signal to noise ratio; Transmitters;
Conference_Titel :
Communications, 1999. APCC/OECC '99. Fifth Asia-Pacific Conference on ... and Fourth Optoelectronics and Communications Conference
Conference_Location :
Beijing, China
Print_ISBN :
7-5635-0402-8
DOI :
10.1109/APCC.1999.824987
