MODULATION SCHEME WITH INCREASED NUMBER OF STATES OF POLARIZATION

摘要

A modulation method for optical communication comprises the step of generating an optical signal modulated between a plurality of different states of polarization and between different phase states. The plurality of states of polarization comprises first states of polarization (SOP1-4). The first states of polarization (SOP1-4) define a single great circle (10) on the Poincaré sphere. The method is characterized in that the plurality of states of polarization further comprise one or more second states of polarization (SOP5- 6) located outside the great circle (10). Such additional second states of polarization increase the symbol alphabet.