Comparison between Conventional OCDMA and Subcarrier Multiplexing SAC OCDMA System Based on Single Photodiode Detection

N A A Ahmad,Mohd Rashidi Che Beson,Syed Alwi Aljunid,M N Junita,Rosdisham Endut,P.J Soh,T Sabapathy,Z.I Abdul Khalib,M Jusoh

doi:10.1051/matecconf/201714001021

N A A Ahmad, Mohd Rashidi Che Beson + Show 7 more

Open Access

https://doi.org/10.1051/matecconf/201714001021

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Abstract

This paper demonstrates the comparison between conventional OCDMA system and subcarrier multiplexing (SCM) SAC-OCDMA system by applying Recursive Combinatorial (RC) code based on single photodiode detection (SPD). SPD is used in the receiver part to reduce the effect of multiple access interference (MAI) which contributes as a dominant noise in incoherent SAC-OCDMA systems. From this analysis, the performance of SCM OCDMA network could be improved by using lower data rates and higher received power. The hybrid SCM OCDMA system shows better performance compare to conventional OCDMA system although the number of users involved is very high. This is because, for hybrid SCM OCDMA system, the number of users can be increased by increasing the number of subcarriers without affect the number of code length and optical codes. Increasing the number of subcarriers will enhance the power consumption by applying hybrid SCM system in OCDMA compared to the conventional OCDMA system. This is because increasing the number of users for hybrid SCM system does not affects the number of code length and the number of optical codes but only increase the number of subcarriers. Thus, hybrid SCM OCDMA system has to increase spectral efficiency and produce better performance compared to conventional of OCDMA system.

Highlights

There are three types of multiplexing techniques in optical system such as Optical code division multiple access (OCDMA), Wavelength Division Multiplexing (WDM) and optical Time Division Multiplexing (TDM)
This paper demonstrates the comparison of conventional OCDMA system between hybrids subcarrier multiplexing (SCM) OCDMA system by applying single photodiode detection (SPD) technique
The implementation of SPD technique can evaluate the performance of hybrid SCM system by employing Recursive Combinatorial code (RC)

Summary

Introduction

There are three types of multiplexing techniques in optical system such as Optical code division multiple access (OCDMA), Wavelength Division Multiplexing (WDM) and optical Time Division Multiplexing (TDM). The use of hybrid Radio Frequency technique over SCMspectral amplitude coding (SAC) Optical Code Division Multiple Access (OCDMA) is proposed to carry the high data over fiber link and to increase the number of users. This enables the reduction of Multi Access Interference (MAl) with high data rate, leading to the increase in the number of active users. We carried out this research by using a hybrid SCM technique by employing SAC OCDMA code sequences. The number of users can be increase by increasing the number subcarrier without effects the number of code length and number of SAC-OCDMA codes

Recursive Combinatorial Code

Theoretical Development of Hybrid SCM OCDMA System Based on SPD Technique

Analysis of Results and Discussion

CONCLUSION