Fig. 7.38 The PLL system for OEO. Here we use the following designations: 20—a laser, 19—a
modulator, 14—the phase-shifter, 13—the photodetector, 15—an amplifier and the RF filter, 16—a
coupler, 22, 28, 29—optical fibers of the PLL system, 23—the photodetector, 30—the second
photodetector and the second amplifier, 24—the third amplifier, 25—the phase detector, 8, 9, 11—
optical couplers, 7, 10, 12—optical fibers, 4—the second modulator, 5, 6, 7, 8, 9, 10, 11, 12—
optical fibers, 1—the external RF oscillator, 2—OEO, 3—the PLL system, 26—an amplifier.
(Patent belonging to authors [27])
7.7 Systems of Frequency and Phase Automatic Control in OEO
453
modulator, 14—the phase-shifter, 13—the photodetector, 15—an amplifier and the RF filter, 16—a
coupler, 22, 28, 29—optical fibers of the PLL system, 23—the photodetector, 30—the second
photodetector and the second amplifier, 24—the third amplifier, 25—the phase detector, 8, 9, 11—
optical couplers, 7, 10, 12—optical fibers, 4—the second modulator, 5, 6, 7, 8, 9, 10, 11, 12—
optical fibers, 1—the external RF oscillator, 2—OEO, 3—the PLL system, 26—an amplifier.
(Patent belonging to authors [27])
7.7 Systems of Frequency and Phase Automatic Control in OEO
453