Convergence of Technologies Enabling Radio Crosslink Missions for Planetary Atmospheric Structures

The atmospheric radio occultation (RO) technique was developed six decades ago for planetary missions and has since resulted in numerous scientific discoveries throughout the Solar System. The traditional experimental configuration utililizes spacecraft communication links with phase-stable radio signals transmitted from a spacecraft orbiting or flying past a planet and received at a ground station after propagating through the atmosphere. Alterations in the phase and amplitude are used to infer properties of that atmosphere. A reverse configuration with a ground-to-spacecraft one-way link has been used with the appropriately instrumented mission to Pluto to overcome severe signal-to-noise ratio limitations. A more recently investigated spacecraft-to-spacecraft occultation technique utilizes UHF communication links between Mars landers and orbiters to measure ionospheric properties