"Hiding" a Low-Intensity 50-Gbit/s QPSK Free-Space Optical Beam That Co-Axially Propagates on the Same Wavelength with a High-Intensity 50-Gbit/s QPSK Optical Beam using Orthogonal Mode Multiplexing

Abstract

We experimentally demonstrate using data-carrying Gaussian beam to "hide" a weaker data carrying OAM beam. A 50-Gbit/s QPSK data link with Q factor above 4.5 is realized for the weak OAM beam when the power difference between Gaussian and OAM beam is 30-dB.