Extended 2D Codes Supporting Multirate and QoS in Optical CDMA Networks With Poisson and Binomial MAI Models

Abstract

In this paper, an extended 2D multiweight multilength optical orthogonal code (MWML-OOC) is proposed and analyzed using both Poisson and binomial distributions of multiple access interference (MAI). We also analyze the performance of 1D and 2D MWML-OOC that can support multirate transmission and quality-of-services (QoS) differentiation in the optical code-division multipleaccess networks. The theory of the 1D MWML-OOC is reviewed where its bit-error rate (BER) performance analysis, based on the binomial model of MAI using the convolution technique, is presented and compared with the well-known Poisson model. The results indicated that the overall performance referred to as BER considering the binomial distribution of MAI is better than that obtained from Poisson-modeled MAI for both 1D and 2D MWML-OOCs. It was also found that the extended 2D MWML-OOC can support a greater number of users with reduced chip times and highly improve the BER performance compared with its 1D and 2D counterparts.

An optical CDMA random access protocol for multi-rate optical networks adopting multi-coding techniques

“…In an incoherent OCDMA system, each user is allocated a unique signature sequence from a family of 0/1 sequences referred to as the optical orthogonal codes (OOCs) that satisfy certain correlation properties [2].…”

Next generation access networks: flexible OCDMA systems and cost-effective chaotic VCSEL sources for secure communications

“…A distinct and worth investigating code, denominated 2-D multi-weight multi-code OOC (2-D MWML-OOC), has been recently proposed in [54]. This code has good correlation properties and large cardinality, and presents a reasonably simple construction algorithm.…”

“…Furthermore, in this 2-D MWML-OOC, the number of wavelengths and code-length and -weight can be chosen independently, which allows arbitrary data rates and QoS differentiation to be achieved. Since 2-D codes normally have short length, they present advantages such as low chip rate and network latency, and high spectral efficiency [54].…”

“…The combination of frequency and time encoding provide better flexibility in code choice, resulting in an increased capacity of the system. Such flexibility allows for reduced code length design without hindering the code cardinality or the system's performance in relation to the 1-D codes [52]- [54], [75]. In addition, the frequency and time encoding can also reach long transmissions at high rates to such an extent that the linear dispersion becomes less critical.…”

“…In addition, it provides greater flexibility in the choice of code parameters and thus are considered an interesting alternative to overcome the shortcomings of 1-D codes. Finally, 2-D codes have additional advantages such as low chip rate and network latency as well as high spectral efficiency, all due to its short code length [54] when compared to 1-D codes.…”