Ranging and Imaging of Spacecraft with the Deep-Space Network's High-Gain Antennas

- Recent interest in cis-lunar space exploration and situational awareness demands accurate detection, ranging, and imaging capabilities to monitor spacecraft in the lunar environment. NASA's 34 meter Beam Waveguide antennas equipped with 20 kW and 80 kW C-band transmitters are ideal for illuminating decommissioned satellites, which enables the application of recently developed algorithms to help determine their range and position in space, and even offering the possibility of generating Doppler-delay images of large spacecraft. This paper describes experiments carried out at Goldstone with NASA's high-gain 34 meter antennas, where decommissioned GOES satellites were illuminated with suitable ranging and image-forming waveforms designed to determine their range and position in space, and form Doppler-delay images capable of resolving the main body, solar panels and instruments on long booms to help identify and classify current and future spacecraft in the cis-lunar environment.