Publication

Abstract : This paper introduces a novel all-optical contention detection circuit utilizing a carrier reservoir semiconductor optical amplifier (CR-SOA) to achieve efficient four-wave mixing (FWM) at 120 Gb/s. Unlike traditional SOAs, which are limited by slow carrier recovery, CR-SOAs leverage a carrier reservoir for rapid gain and phase recovery, making them suitable for high-speed applications. The proposed circuit detects contention between data streams at different wavelengths using only two input signals, eliminating the need for an external pump signal. Four-wave mixing (FWM) in CR-SOA has been employed for detecting contention at different wavelengths. This simplification is especially beneficial for dense wavelength division multiplexing (DWDM) systems, where adding pump signals can complicate integration. Unlike other contention detection circuits that use multiple SOAs, the proposed circuit employs a single CR-SOA, thereby eliminating distortions caused by cascading nonlinear elements. Performance analysis is conducted by varying one wavelength while keeping the other constant to reflect real-world contention scenarios. Additionally, this study examines how the quality factor of the contention detection circuit varies with the frequency difference between the original signal and the contending signal, providing a novel perspective on performance variation under dynamic frequency conditions. The results demonstrate the circuit's effectiveness across varying input power levels, data rates, and CR-SOA parameters, offering a streamlined and resource-efficient solution for contention detection.