Optical Fiber Technology | 2021
Robust ICA based mode demultiplexing
Abstract
Abstract In this paper, we present a mode demultiplexing algorithm based on robust independent component analysis (ICA) in electrical domain. Multi-mode fiber (MMF) based spatial division multiplexing system is modeled as a behavioral model. Different modes can carry the data to increase the system capacity with the proposed algorithm. In the system, two orthogonal frequency division multiplexing (OFDM) signals are modulated on two modes by two vertical cavity surface emitting lasers (VCSEL) and then coupled into the MMF with an optical coupler. Two channel signals are separated by the proposed robust ICA mode demultiplexing algorithm after photodetectors at the receiver side. The OFDM signals can be demodulated successfully after the separation. Compared with a single mode transmission in MMF, the transmission performance of two mode channels is not degraded significantly with the proposed mode demultiplexing algorithm. Our results show that the proposed algorithm can carry out the modes demultiplexing successfully and the cross-talk between modes can be reduced or be negligible after processing. It also demonstrates a new application of ICA algorithm in the electrical time-domain mode demultiplexing.