The primary focus of this program is to enable the development of a chip-scale integrated Indium Phosphide based rad hard RZ-DPSK transmitter for NASA for use in compact optical modems for the international space station. The program goal is the integration of tunable laser, optical modulators, gating and booster SOA into a single monolithic chip and the surrounding compact package to generate a small footprint transmitter for NASA use in the ISS, and potentially further into space subsystems, pico satellites, and space vehicles. Chip-scale integrated miniaturized, yet high performance tunable optical transmitters can significantly impact a wide range of applications in addition to NASA's ISS space communication and control needs. These applications include other space and terrestrial communications applications, including both free-space and fiber optic links, a range of sensing applications and potential optical waveform generating sources. Given this potential demand, it is expected that the annual market for chip-scale integrated transmitters could grow to many tens of millions of dollars.