Title :
Multi-Code MC-CDMA Using Joint CDTD and Inter-Code Interference Cancellation
Author :
Takeda, Kazuaki ; Tomeba, Hiromichi ; Wang, Jiangzhou ; Adachi, Fumiyuki
Author_Institution :
Dept. of Electr. & Commun. Eng., Tohoku Univ., Sendai
Abstract :
In multicarrier code division multiple access (MC-CDMA), a good bit error rate (BER) performance can be achieved by using frequency-domain equalization (FDE) based on the minimum mean square error (MMSE) criterion. However, the presence of residual inter-code interference (ICI) after MMSE-FDE and despreading degrades the BER performance of the multi-code MC-CDMA. The use of ICI cancellation can improve the BER performance of the multi-code MC-CDMA. To further improve the BER performance, transmit diversity technique is effective. In this paper, cyclic delay transmit diversity (CDTD) is considered. CDTD can achieve the frequency diversity gain, whereas the well-known space-time transmit diversity (STTD) can achieve the antenna diversity gain owing to the space-time coding and provide a better BER performance than CDTD. It is shown in this paper that the performance degradation of CDTD is mainly due to the residual ICI after MMSE-FDE. In order to achieve a good BER performance, the multi-code MC-CDMA using joint CDTD and ICI cancellation is proposed, and its BER performance is evaluated by computer simulation.
Keywords :
code division multiple access; diversity reception; error statistics; interference suppression; radiofrequency interference; space-time codes; BER performance; antenna diversity gain; bit error rate performance; cyclic delay transmit diversity; frequency diversity gain; frequency-domain equalization; minimum mean square error; multicarrier code division multiple access; multicode MC-CDMA; residual intercode interference cancellation; space-time coding; transmit diversity technique; Bit error rate; Degradation; Delay; Diversity methods; Frequency diversity; Interference cancellation; Mean square error methods; Multicarrier code division multiple access; Performance gain; Transmitting antennas;
Conference_Titel :
Vehicular Technology Conference, 2008. VTC 2008-Fall. IEEE 68th
Conference_Location :
Calgary, BC
Print_ISBN :
978-1-4244-1721-6
Electronic_ISBN :
1090-3038
DOI :
10.1109/VETECF.2008.194