Patent ID: 8922772

Claim:
An optical system comprising: a master oscillator generating a signal beam; a master beam splitter for splitting the signal beam into a plurality of fiber beams; a plurality of polarization actuators each receiving one of the fiber beams, said polarization actuators providing polarization control of the fiber beams; a plurality of phase modulators each receiving one of the fiber beams, each phase modulator modulating the fiber beam with a unique time-dependent phase dither profile signal having a zero time-averaged mean and a zero time-averaged correlation to the other phase dither profile signals, each phase modulator providing phase control of the fiber beams; a plurality of fiber amplifiers each receiving a fiber beam from one of the phase modulators, said fiber amplifiers amplifying the fiber beams; a beam combiner combining the amplified fiber beams into a combined beam; a sample beam splitter for separating a low power sample beam from the combined beam; a reference beam provided by the master beam splitter; a mixing device responsive to the sample beam and the reference beam, said mixing device providing an in-phase optical signal including a superposition of the sample and reference beams with a relative phase difference of 0° and a quadrature phase optical signal including a superposition of the sample and reference beams with a relative phase difference of 90°; a first photodetector responsive to the in-phase optical signal and converting the in-phase optical signal to an in-phase electrical signal; a second photodetector responsive to the quadrature phase optical signal and converting the quadrature phase optical signal to a quadrature phase electrical signal; a plurality of phase mixing circuits including a separate phase mixing circuit for each fiber beam and being responsive to the in-phase electrical signal, each phase mixing circuit measuring the phase of the phase dither signal for its fiber beam and providing a phase error signal; a plurality of phase controllers including a separate phase controller for each fiber beam, each phase controller being responsive to one to the phase error signals and controlling the phase modulator for that fiber beam to null the phase error signal; a plurality of polarization demultiplexer circuits including a separate polarization demultiplexer circuit for each fiber beam and being responsive to the quadrature phase electrical signal, each polarization demultiplexer circuit measuring correlations between the quadrature phase electrical signal and the phase dither signal of its respective fiber beam and providing a polarization amplitude signal; and a plurality of polarization controllers including a separate polarization controller for each fiber beam, each polarization controller being responsive to one to the polarization amplitude signals and controlling the polarization actuator for that fiber beam to maximize the polarization amplitude signal.