Qualification of the Solid-State Laser Systems for the GEDI Altimeter Mission

摘要

The Global Ecosystems Dynamics Investigation (GEDI) Lidar Mission will employ three lasers systems internally developed, built, and tested by the NASA Goddard Space Flight Center Lasers and Electro-Optics Branch. Once installed on the Japanese Experiment Module (JEM) on the International Space Station (ISS), the lasers, each coupled with a Beam Dithering Unit (BDU) will produce three sets of staggered footprints on the Earth's surface to accurately measure global biomass. Each of the lasers is a heritage Nd:Yag solid state design required to put out Q-switched pulses at a rate of 242 Hz with a minimum 10 mJ per pulse at a 1064 nm wavelength. During the project, an engineering test unit (ETU) was also built and tested to pave the way for the laser systems to be used in space. We report on the technical and programmatic requirements that drove the design and development of the lasers. Also presented is an update of the performance of the engineering test unit qualification and life-testing along with the status of the space flight lasers.