Patent ID: 6999688

Claim:
A method of processing a received optical signal from an optic fiber, the received optical signal carrying user information, the method comprising: splitting by way of a splitter the received optical signal based on polarization into a fist optical signal and a second optical signal; converting the first optical signal into a corresponding first electrical signal; converting the second optical signal into a corresponding second electrical signal; applying radio frequency detection to the first electrical signal to generate a third electrical signal; applying radio frequency detection to the second electrical signal to generate a fourth electrical signal; combining the third electrical signal and the fourth electrical signal to form a fifth electrical signal that carries the user information; low-pass-filtering the fifth electrical signal to generate a filtered fifth electrical signal; amplifying the filtered fifth electrical signal to generate an amplified fifth electrical signal; and processing the amplified fifth electrical signal to align polarizations of the received optical signal with a principal axis of the splitter; wherein the first optical signal and the second optical signal are aligned with the principal states of polarization of the optic fiber.