System and method for receiving coherent, polarization-multiplexed optical signals

A device, polarization diversity receiver and the receiving of said optical signal of the method. In one embodiment, wherein the device comprises: The optical device; the optical device is configured for separating and a synchronization and quadrature device for optical signal, wherein in-phase device for wherein the luminous efficiency, wherein the quadrature device for wherein the second luminous efficiency, (2) on the first luminous efficiency coupled to the reception of the first polarization and diffuser (3) and second luminous efficiency coupling is arranged on the light the second polar diffuser.