Substantial OBI Noise Reduction in MM Fiber Network

Optical beat interference is one of the major problems impairing upstream transmission in passive optical networks. In this letter, a theoretical study indicates that if single mode fibers are replaced with multimode fibers, the interference is reduced at least by the factor of N, where N is the number of modes propagating. In the experiment carried with two types of lasers, a reduction of beating noise ~10 dB is observed. Even greater reduction is expected in the first transmission window.