Journal of Optical Communications

Performance Enhanced Asynchronous Optical CDMA Systems using Double Hard-limiters and FEC Codes

Anand Kumar Srivastava, Subrat Kar, Virander Kumar Jain

Published Jan 1, 2004• 0 citations

Abstract

Optical code division multiple access (OCDMA) systems are generally interference limited. To alleviate the adverse effect of optical multiple access interference (OMAI), use of forward error correcting (FEC) codes and optical double hard-limiters (DHLs) are explored. The system analysis is carried out under chip synchronous case among different users with PIN+OA as the receiver. The analysis incorporates the effect of amplifier noise, thermal noise and OMAI. It is observed that optical CDMA systems with FEC and double hard-limiters give rise to satisfactory performance even when the number of simultaneous users is large. It has been observed that with the usage of DHLs there is a significant improvement in the performance. When FEC is also used along with DHLs, there is slight enhancement in the performance.

DOI: 10.1515/joc.2004.25.6.250

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