Regular ArticlesVariable weight spectral amplitude coding for multiservice OCDMA networks

- Variable weight MS (VW-MS) code is developed to support different QoS in optical domain.
- VW-MS code is compared with its counterparts considering cross-correlation and code length.
- VW-MS maintains cross-correlation of 1 between all pair of codewords with an optimum code length.
- Mathematical model is developed to show the performance of VW-MS code for triple-play service.

The emergence of heterogeneous data traffic such as voice over IP, video streaming and online gaming have demanded networks with capability of supporting quality of service (QoS) at the physical layer with traffic prioritisation. This paper proposes a new variable-weight code based on spectral amplitude coding for optical code-division multiple-access (OCDMA) networks to support QoS differentiation. The proposed variable-weight multi-service (VW-MS) code relies on basic matrix construction. A mathematical model is developed for performance evaluation of VW-MS OCDMA networks. It is shown that the proposed code provides an optimal code length with minimum cross-correlation value when compared to other codes. Numerical results for a VW-MS OCDMA network designed for triple-play services operating at 0.622 Gb/s, 1.25 Gb/s and 2.5 Gb/s are considered.