Using Turbo Codes and Non-Gaussian Interference to Improve Spectral Efficiency in M-ary Optical CDMA Networks

Conference: TURBO - CODING - 2006 - 4th International Symposium on Turbo Codes & Related Topics; 6th International ITG-Conference on Source and Channel Coding
04/03/2006 - 04/07/2006 at Munich, Germany

Proceedings: TURBO - CODING - 2006

Pages: 6Language: englishTyp: PDF

Personal VDE Members are entitled to a 10% discount on this title

Garba, Aminata A.; Bajcsy, Jan (Dept. of Electrical and Computer Engineering, McGill University, 3480 University St., Montreal, Quebec H3A 2A7, Canada)

We considers turbo-coded optical CDMA network transmission when single-user detection and single-user decoding are performed at the receiver. We use turbo codes, M-ary optical spreading codes and soft-decision demodulation to achieve very high spectral efficiencies over 0.4 bits per optical CDMA chip. In particular, we consider recently-proposed M-ary OCDMA transmission with non-equiprobable chips. We observe for this approach that the multi-user interference has a strongly reduced and uniquely non-Gaussian structure. Consequently, we propose a novel soft-decision single-user optical CDMA signal detector that takes advantage of this specific interference structure. We also present simulation results of a turbo-coded M-ary OCDMA network transmission that allows above mentioned spectral efficiencies.