Abstract: The present invention is directed towards systems and methods that include an optical polarization scrambler or depolarizer after the optical transmitter. In this manner, the optical signal is depolarized. Accordingly, the noise peaks that were translated from Guided Acoustic-Wave Brillouin Scattering (GAWBS) by the devices with polarization dependent loss or gain is mitigated in order to have little effect on the quality of the RF signal carried by lightwave.

Abstract: A method is provided for controlling the output frequency of a laser having a lasant gain medium which is characterized by at least two gain curve distributions over a range of lasant frequencies and having a laser cavity which is characterized by at least one resonant frequency within one gain curve distribution. The method comprises the steps of: locating in the laser cavity a first Lyot filter which has a transmission band which favors the frequency range of one gain curve distribution in preference to the frequency range of the other gain curves; and locating in the cavity a second Lyot filter which has a transmission band which favors said one resonant frequency within the frequency range of the one gain curve, whereby an essentially single frequency output is obtained.