Simulation-Based Optical Threshold Component Design for Mitigating Four-Wave Mixing Effects in WDM Radio Over Fiber Systems

Abstract

AbstractThe gigantic demand on high bandwidth and capacity has triggered the need to use the radio over optical fiber (RoF) systems. RoF systems offer several attractive features such as low attenuation loss, large bandwidth, less interference, etc., which can improve the communication system reliability and achieve high data rates. However, the RoF system suffers from linear and nonlinear fiber impairments, which result in signal distortion. Several solutions have been proposed to overcome linear impairments; on the other hand, the nonlinear impairments issue is still a challenging problem in RoF communication systems. Four-wave mixing (FWM) is the most dominating nonlinear impairments that impacts the performance of optical fiber communication systems and the RoF systems as well. In this article, we present a strategy to mitigate the FWM effect in wavelength division multiplexing (WDM) RoF systems. Specifically, we study the effect of FWM under high transmit power levels over long transmission distances. This proposed strategy aligns the optical and radio link parameters to alleviate the FWM effects. To achieve this objective, the impact of WDM RoF system parameters such as wavelength ($\lambda_i$), transmitted power, etc., on system performance is investigated. The main performance metrics are the total signal-to-noise ratio (SNR), optical SNR (OSNR), Q-factor, and bit error rate (BER). Given these metrics, our proposed strategy defines an optical threshold level that applies to the optical threshold component to get rid of the undesired signals generated by the FWM effect.