Characterization of a High-Power Fiber Master Oscillator Power Amplifier (MOPA) Laser as an Optical Communications Transmitter

Deep-space optical communications requires high-power laser transmitters with good beam quality that can be modulated at fairly high data rates. We report here on the performance of a fiber-based master oscillator power amplifier (MOPA) laser, commercially developed to JPL requirements with specifications derived from a Mars mission optical downlink scenario. The laser demonstrates up to 1.6-kW peak power and an average power of around 10 W at 1060 nm with pulse repetition rates from 3 to 30 MHz and diffraction-limited beam quality. A programmable highrate pulse-position modulator (PPM) also was developed as a data source, and the performance of the laser under variable pulse delays, as required for transmitting data streams, was measured.