The deep space optical communications (DSOC) flight terminal

NASA’s Deep Space Optical Communications (DSOC) Project, implemented by the Jet Propulsion Laboratory (JPL), has successfully completed the first year of its technology demonstration, delivering high-rate optical downlinks for the first time from deep space over spacecraft distances ranging from 0.1 to 3 astronomical units (AU). The heart of the flight terminal is an essentially free-floating 22 cm telescope and photon-counting camera, mounted on a platform that is steered by Lorentz-force actuators. The hardware also includes a 4 Watt transmit laser and associated electronics. The instrument software and firmware algorithms detect and track a modulated optical uplink beacon, decode data modulated on that beacon signal, point the downlink laser, and encode pulse position modulated (PPM) data for the optical downlink. These hardware elements are described, along with the firmware and software signal processing algorithms. The concept of operations for the flight terminal is also described.