INTENSITY NOISE MITIGATION METHODS

Intensity Noise Mitigation Methods for Spectral-Amplitude Coding (SAC) Optical Code-Division Multiple Access (OCDMA) Systems

Abstract

In this review paper we try to explore the concept of Optical Code-Division Multiple Access (OCDMA) Systems in a holistic context. The main focus of the research is on the review of 18 references attached and its relation with intensity noise mitigation methods. The research also analyzes many aspects of Spectral-Amplitude Coding (SAC) and tries to gauge its effect on Optical Code-Division Multiple Access (OCDMA) Systems. Finally the research describes various factors which are responsible for different aspects mentioned in the given articles that are to be analyzed and tries to describe the overall effect of Spectral-Amplitude Coding (SAC) Optical Code-Division Multiple Access (OCDMA) Systems on Intensity Noise Mitigation Methods.

Intensity Noise Mitigation Methods for Spectral-Amplitude Coding (SAC) Optical Code-Division Multiple Access (OCDMA) Systems

Introduction

This review paper analyzes the different articles provided. These articles are based on the intensity noise mitigation methods for Spectral-Amplitude Coding (SAC) Optical Code-Division Multiple Access (OCDMA) Systems. According to Ghazisaeidi (2010)in article “Capacity of SOA-Assisted SAC-OCDMA”, the performance of spectral amplitude coded optical code-division multiple access (SAC-OCDMA) systems is severely curtailed by the excess intensity noise of the incoherent thermal-like light source. To mitigate the intensity noise, various solutions have been proposed. In one approach, the optical bandwidth of the frequency bins of all codes are optimized to trade-off noise reduction (due to optical bandwidth enlargement) when using wide overlapping optical bins against enhanced beat noise due to bin overlapping. Another approach is to use intensity noise suppression offered by saturated semiconductor optical amplifiers (SOAs). SOA-based noise suppression has proven useful in spectrum-sliced wavelength- division-multiplexed (SS-WDM) systems. In OCDMA, so as not to add features high-speed electronic processing, it is important to implement the encoding in the optical domain rather than in the electrical field. Several proposals exist in the literature to make this happen, and this for different types of encoding OCDMA.

Review Of The Research Articles

Codes particularly suited to the DS-OCDMA are developed and analyzed in detail by Hussein et. al. (2011) mentioned in an article named “Development of a new code family based on SAC-OCDMA system with large cardinality for OCDMA network”. They are called optical orthogonal codes (OOC) because of their properties autocorrelation and cross correlation. Indeed, a DS-OCDMA decoder standard compensates for delays suffered by a pulse encoded and reconstructed autocorrelation peak. OOC codes are called orthogonal when the maximum value of cross correlation and autocorrelation lobe is bounded, and this, among all family codes. The advantages of using Optical Code Division Multiple Access (OCDMA) techniques are to provide moderate security communication and allow multiple users to access optical network with a sharing bandwidth mechanism. Nevertheless, the performance of time-domain OCDMA systems is limited by the influence of Multi- Access Interference (MAI) . In a spectral-amplitude-coding OCDMA (SAC-OCDMA) system, the effect of MAI can, in theory, be removed by utilizing codes with fixed in-phase cross-correlations.

In one of the article of Penon (2009) it is mentioned that ...