WIDE DYNAMIC RANGE OPTICAL LINK USING DSSC LINEARIZER

摘要

A wide dynamic range optical link using a double sideband suppressed carrier linearizer, the link comprising a laser source for producing a lightwave carrier output at a predetermined power level and wavelength, a double sideband suppressed carrier optical modulator having the lightwave carrier as a first input and an RF information- bearing signal as a second input, said double sideband suppressed carrier modulator comprising a signal splitter for dividing the lightwave carrier into primary and secondary carriers, a Mach-Zehnder optical modulator producing a modulated signal comprising information sidebands and a primary carrier component, a feedback controlled phase shifter in which the secondary carrier is shifted 180 degrees from the primary carrier phase, a signal combiner into which are input the modulated signal and the phase shifted secondary carrier, the combination of said signals causing the controlled suppression of the carrier component in the output of the signal combiner. A feedback loop controls the phase shifter. The double sideband suppressed carrier modular produces a suppressed carrier modulated signal output that is coupled to a linear optical amplifier for increasing the effective modulation index of the modulated signal output from the suppressed- carrier modulator. The output of the linear optical amplifier is connected to an optical fiber medium for transmission of the modulated signal.