Electronic dispersion compensation for optical transceivers using directly-modulated Fabry-Perot laser

Abstract

Substituting the laser source in an optical communication network with a more cost-effective alternative can significantly reduce the overall construction costs of the network. Specifically, low-cost Fabry-Perot (FP) laser can replace distributed feedback (DFB) lasers, which is commonly used for short-reach optical networks such as passive optical network (PON). However, FP lasers present challenges such as the emission of light across multiple wavelengths and Mode Partition Noise (MPN), leading to chromatic dispersion and time-variant intensity noise. Traditional optical solutions like Dispersion Compensation Fiber (DCF) address these issues but are economically inefficient. This study introduces an advanced Electronic Dispersion Compensation (EDC) system to effectively compensate for signal distortion induced by FP laser. The research models FP laser nonidealities and applies a receiver-side finite impulse response (FIR) filter with LMS adaptation, verifying improvements in signal integrity. A track-and-hold based analog FIR filter is designed and simulated, achieving a two-and-a-half-fold increase in eye height for $10Gbps$ data, demonstrating a cost-effective approach to enhancing optical network performance.