Optical CDMA system with the least multiple access interference under arbitrary restrictions

Abstract

The most important issue in asynchronous optical code division multiple-access (CDMA) systems is the multiple access interference (MAI), which is caused by the non-ideal orthogonal property of optical codes and which is the main factor of the bit error. In this paper, we propose and examine an extremely versatile optical code, the adaptive resonance code (ARC), which has the least MAI under arbitrary restrictions arising from designing optical CDMA systems. The analytical results show that ARC has near-ideal MAI and that the available number of nodes in a system is doubled without changing the coding scheme and/or physical structure of the system at the cost of little performance degradation. In the traditional method of implementing an optical CDMA system, components such as optical sources and encoders/decoders are designed after choosing an optical code. When ARC is used, it is also possible that components are first designed with their own specialties and then an optimal code set for the components is generated. (C) 2003 Elsevier B.V. All rights reserved.