Signal processing in a Mach-Zehnder intensity modulator for coherent and incoherent light using copropagating and counterpropagating electrical signals

A new application of a Mach-Zehnder intensity modulator is proposed for both radio frequency and baseband signal processing. Accessing both input and output electrical ports, the equivalent of a two-tap transversal filter is easily realized allowing sine- and cosine-shape frequency responses. As only unidirectional optical propagation is utilized, the optical insertion loss can be kept low. Both coherent and incoherent light can be processed.