Summary

Proceedings of the 2012 International Symposium on Nonlinear Theory and its Applications

2012

Session Number:C2L-C

Session:

Number:662

Performance of Chaotic CDMA System implemented on Software-Defined Radio System

Hisashi Watanabe,  Yuichi Omori,  Mikio Hasegawa,  Kazuyuki Aihara,  

pp.662-665

Publication Date:

Online ISSN:2188-5079

DOI:10.15248/proc.1.662

PDF download (636.8KB)

Summary:
We implement the chaotic code division multiple access (CDMA) system using the software-defined radio (SDR) technology and evaluate the performance of the implemented system. In the researches on the chaotic CDMA, it has been shown theoretically that the bit error rate (BER) can be reduced by using chaotic sequences with negative autocorrelation. Furthermore, by more realistic analysis including the band-limiting filter, it has been clarified that the BER can be improved by using the Gaussian filters better than the general case with the Nyquist filter, when we use the ideal chaotic spreading codes with negative autocorrelation. The experimental results using our implemented system on the SDR clarify that the Gaussian filter and the spreading sequence with a specific negative autocorrelation leads to the lowest BER in band-limited asynchronous CDMA system.

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