Patent attributes
The present invention relates to optical transmitters, transceivers, and transponders used for transmission of information or data in any form through a physical medium dependent (PMD) network. The speed of such networks depends, in part, on the density of information that can be transmitted through the physical medium. Optical transmitters or transceivers can be used to transmit multiple independent signals simultaneously through the same medium using different directions or axes of polarization, where the difference in the directions or axes of polarization can be used to distinguish the multiple signals at the receiver. In this invention, we use a master laser (l0) to synchronize two slave lasers (l1 and l2) by its x-polarization and y-polarization components of carrier, respectively, so that two slave lasers can be enforced to lock on exactly the same wavelength l0 with perpendicular polarization directions.
