International Mars Ice Mapper Communication System

The Italian Space Agency (ASI) and Thales Alania Space in Italy (TAS-I) in the context of the International Mars Ice Mapper (I-MIM) mission and in collaboration with the NASA Jet Propulsion Laboratory (JPL) are studying an innovative multi-band Communication Subsystem designed to deliver scientific data of at least 500 Gbit per day from the mission’s three elements (E): a main orbiter (E1), a demonstration lander (E2), and a freeflying smallsat (E3). The planned E1 instruments are a polarimetric synthetic aperture radar (SAR) in L-band, a Very High Frequency (VHF) sounder, and a submillimeter sounder. The E3 orbiter would carry a high-resolution imager. All of these next-generation sensors would generate high volumes of data and require large data-rate (>100 Mbps) acquisition. With analysis and definition of mission scenarios during its concept phase, the mission team has identified two main communication links. The Direct to Earth (DTE) link would deliver the science data and telecommand and telemetry at a high data rate primarily in Ka-bands (32 GHz) and in X-bands, with data transmission above 10 Mbps with Deep Space Network ground stations. The preliminary defined architecture anticipates that the 6-m aperture Large Deployable Reflector antenna (LDR) would support both DTE and the SAR instrument. The other main link under definition is the Proximity Link, which would support the relay of science data from the E3 smallsat to the main orbiter through X band for subsequent DTE links. This proximity link would potentially be available to relay data from future Mars orbiters and next-generation rovers and landers on the surface. A UHF proximity link would be onboard to relay data from legacy users on the surface already at Mars, as well as potentially support I-MIM’s E2 lander. While both UHF and X-band are the primary considered bands for the proximity link, the mission team is also considering Ka-band and optical links to take into account the evolution of future exploration missions. With the goal of identifying and characterizing accessible, near-surface water ice in the mid latitudes of Mars, the I-MIM mission is a multilateral collaboration being developed by the Agenzia Spaziale Italiana (ASI), the Canadian Space Agency (CSA), the Japan Aerospace Exploration Agency (JAXA), and the National Aeronautics and Space Administration (NASA).