Patent ID: 8073326

Claim:
An optical communication system for optical communicating based on polarization division multiplexing (PDM), comprising: a PDM transmitter to produce light comprising (1) a first optical signal carrying a first data channel in a first optical polarization and at an optical signal wavelength, (2) a second optical signal carrying a second data channel at a second optical polarization different from the first optical polarization and at the optical signal wavelength, and (3) light at a monitor signal wavelength different from the optical signal wavelength and in the first optical polarization; a transmission link to receive and transmit the light from the PDM transmitter; and a PDM receiver to receive light from the transmission link and comprising: a dynamic polarization controller to control polarization of the received light in response to a control signal to produce output light; a polarization beam splitter to split the output light from the dynamic polarization controller into (1) a first beam comprising the first optical signal at the optical signal wavelength and (2) a second beam comprising a second optical signal at the optical signal wavelength, wherein the first and second beams are in orthogonal polarizations to each other; a monitor beam splitting unit in an optical path of the first beam to split the first beam into (1) a monitor beam at the monitor signal wavelength and (2) the first optical signal; a first optical detector to receive and detect the first optical signal; a second optical detector to receive at least a portion of the second beam to detect the second optical signal; an optical monitor detector to receive and detect the monitor beam; and a feedback control unit to produce the control signal based an output of the optical monitor detector to control the polarization of light to the polarization beam splitter to increase optical power of the monitor beam detected at the optical monitor detector and to separate the first data channel and the second data channel into the first optical signal and the second optical signal, respectively.