DocumentCode :
408154
Title :
A chip-interleaving pattern retaining orthogonality in DS-CDMA systems: application to the multicode downlink
Author :
Hardouin, Eric ; Laot, Christophe
Author_Institution :
Signal & Commun. Dept., Ecole Nat. Superieure des Telecommun. de Bretagne, Brest, France
Volume :
4
fYear :
2003
fDate :
6-9 Oct. 2003
Firstpage :
2401
Abstract :
Interleaving the chip-level sequence resulting from spreading before transmission in direct spread code division multiple access (DS-CDMA) systems have been reported to allow significant improvements over conventional (nonchip-interleaved) DS-CDMA. This transmission scheme has been shown to be of particular interest when used in conjunction with iterative receivers, allowing performance close to the multiple access (MAI) and intersymbol (ISI) interference-free case to be reached. This paper addresses the application of chip-interleaving to existing or near-future DS-CDMA systems. An interleaving pattern is introduced that allows the orthogonality property to be retained between interleaved and noninterleaved signals. In addition, a low-complexity receiver based on iterative channel equalization is designed for the multicode downlink of chip-interleaved DS-CDMA systems. Numerical simulations show that used in conjunction with the proposed interleaving scheme, the proposed receiver allows the interference-free performance of the noninterleaved case to be attained.
Keywords :
3G mobile communication; block codes; code division multiple access; interleaved codes; intersymbol interference; iterative methods; multipath channels; radio links; radio receivers; spread spectrum communication; DS-CDMA; ISI; MAI; chip-interleaving; chip-level sequence; direct spread code division multiple access; intersymbol interference; iterative channel equalization; iterative receiver; multicode downlink; multiple access interference; 3G mobile communication; Context; Downlink; Interleaved codes; Intersymbol interference; Multiaccess communication; Multiple access interference; Numerical simulation; Signal design; Signal generators;
fLanguage :
English
Publisher :
ieee
Conference_Titel :
Vehicular Technology Conference, 2003. VTC 2003-Fall. 2003 IEEE 58th
Conference_Location :
Orlando, FL, USA
ISSN :
1090-3038
Print_ISBN :
0-7803-7954-3
Type :
conf
DOI :
10.1109/VETECF.2003.1285960
Filename :
1285960
Link To Document :
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