Development of Low SWAP Laser Transmitters at 1262nm and 1571nm

This work has sought to develop distributed feedback (DFB) diode-laser concepts and technologies necessary to facilitate NASA’s upcoming Active Sensing of CO2 Emissions over Nights, Days, and Seasons (ASCENDS) mission. The ASCENDS mission requires the simultaneous measurement of the CO2 number density column and the O2 number density column to derive the average XCO2 column. NASA Langley Research Center is working on CW fiber laser based Laser Absorption Spectrometer technique for sensing CO2 in the 1571nm spectral band and O2 in the 1262nm spectral band. Efficient and compact and reliable seed laser and fiber amplifier modules are being developed to meet operational and payload challenges. Specifically, a modified-COTS DFB laser module, incorporating a low-noise variable laser bias current supply and low-noise variable temperature control circuit, has been developed. A prototype compact and efficient tunable DFB laser transmitter operating in the 1262nm spectral band has been built and tested. This paper describes the design features and performance characteristics of the 1262nm of a low Size, Weight and Power (SWAP) transmitter including experimental data. In addition, we will discuss recent further development of laser modules for CO2 sensor operating at 1571nm.