Fiber interferometric communications using mach-zehnder interferometer topology

A simple concept of fiber optic communication topology using Mach-Zehnder interferometer is presented. This kind of communication can be used for secure encryption-key distribution or secure point-to-point full-duplex data-transfer communication. In both interferometric-communication applications standard optical components and single-mode fibers are used. Maximum fiber length is dependent on system noise, which must not exceed the interference pattern.