Polarization Dependence of a 100G Simplified PolMux Heterodyne Coherent Receiver for Optical Access Networks

Next-generation optical access networks require advanced technologies to support 50–100 Gbps links, addressing a growing bandwidth demand [1]. Traditional IM/DD systems face limitations like poor sensitivity, bandwidth constraints and frequency fading, which make coherent receivers a promising alternative: they can improve optical power budgets, enhance spectral efficiency, and mitigate chromatic dispersion issues. However, their cost remains a challenge for PONs due to the need for additional components like local oscillator (LO) lasers and polarization management [2]. In a previous work, we presented an independent polarization receiver designed to operate as a low-cost simplified PolMux 50G heterodyne coherent receiver using 10G electronic components and automatic PolMux channel recovery [3]. In this work, we evaluate the performance of this novel receiver architecture under randomly varying States of Polarization (SOP) of the incoming signal. Additionally, we implement and enhanced Digital Signal Processing (DSP) to overcome the polarization instability and, additionally, increase the spectral efficiency.