Title :
Application of cyclic delay transmit diversity to uplink 2-dimensional block spread CDMA with frequency-domain equalization
Author :
Yu, Qiyue ; Meng, Weixiao ; Liu, Bo ; Adachi, Fumiyuki
Author_Institution :
Dept. of Commun. Eng., Harbin Inst. of Technol., Harbin, China
Abstract :
The presence of the multi-access interference (MAI) limits the uplink performance of code division multiple access (CDMA). 2-dimensional (2D) block spread CDMA makes it possible to achieve MAI free uplink transmission while obtaining the frequency diversity gain by using low-complexity single-user frequency-domain equalization (FDE). To further improve the uplink transmission performance, the transmit diversity technique can be used. Cyclic delay transmit diversity (CDTD) can strengthen the frequency-selectivity of the channel. In this paper, we apply CDTD to 2D block spread CDMA with MMSE-FDE. The achievable uplink BER performance is evaluated by computer simulation for both direct sequence CDMA and multi-carrier CDMA. It is shown that CDTD can offer improved uplink BER performance in a frequency-selective uplink channel.
Keywords :
code division multiple access; equalisers; radiofrequency interference; 2-dimensional block spread CDMA; code division multiple access; cyclic delay transmit diversity; direct sequence CDMA; frequency diversity gain; frequency-selective uplink channel; low-complexity single-user frequency-domain equalization; multi-access interference; multi-carrier CDMA; Bit error rate; Computer simulation; Delay effects; Fading; Filters; Frequency diversity; Multiaccess communication; Multicarrier code division multiple access; Multiple access interference; Performance gain; 2-Dimensional block CDMA; CDTD; MAI; fading channel;
Conference_Titel :
Personal, Indoor and Mobile Radio Communications, 2009 IEEE 20th International Symposium on
Conference_Location :
Tokyo
Print_ISBN :
978-1-4244-5122-7
Electronic_ISBN :
978-1-4244-5123-4
DOI :
10.1109/PIMRC.2009.5449845
