MULTILEVEL POLARIZATION SHIFT KEYING BY USING DATA INDUCED POLARIZATION SWITCHING

A scheme to generate a 4-POLSK-tetrahedron signal from an equidistant four-level FSK signal is presented. For this purpose the transmitter l aser equally excites the two polarization modes of a hibi fiber. This fiber is spliced at 45-degrees to a second hibi fiber with half the le ngth of the first. In this scheme different optical frequencies are tr anslated in certain states of polarization. The scheme is in principle passive. The insertion loss and complicated driving scheme of a polar ization modular are avoided. The viability of the scheme was demonstra ted with simulations and an experiment.