Title :
Asynchronous Multi-Carrier DS-CDMA with UCHT-Based Complex Spreading Sequences
Author :
Gu, Zhenghui ; Xie, Shoulie ; Rahardja, Susanto
Author_Institution :
Inst. for Infocomm Res.
Abstract :
Quadriphase complex sequences based on unified complex Hadamard transform (UCHT) are orthogonal and easy to generate S. Rahardja et al. (2003). There are sixty-four sets in UCHT-based sequences. Some sets of UCHT sequences provide better autocorrelation properties than orthogonal Walsh-Hadamard (WH) sequences. In this paper, UCHT-based sequences are applied as spreading sequences in an asynchronous MC-DS-CDMA system. The bit-error rate (BER) performance of the underlying system with complex spreading sequences is investigated and simulation results show that the asynchronous MC-DS-CDMA system spread by UCHT sequences outperforms that spread by WH sequences in frequency selective fading channel
Keywords :
Hadamard transforms; Walsh functions; code division multiple access; error statistics; fading channels; spread spectrum communication; BER; UCHT; asynchronous multi-carrier DS-CDMA; bit-error rate; complex spreading sequences; frequency selective fading channel; orthogonal Walsh-Hadamard sequences; quadriphase complex sequences; unified complex Hadamard transform; Autocorrelation; Bit error rate; Fading; Frequency conversion; Frequency division multiplexing; Mobile communication; Multiaccess communication; Multicarrier code division multiple access; OFDM; Wideband;
Conference_Titel :
Vehicular Technology Conference, 2006. VTC 2006-Spring. IEEE 63rd
Conference_Location :
Melbourne, Vic.
Print_ISBN :
0-7803-9391-0
Electronic_ISBN :
1550-2252
DOI :
10.1109/VETECS.2006.1683054
