49th AIAA Aerospace Sciences Meeting including the New Horizons Forum and Aerospace Exposition AIAA 2011-330 4 - 7 January 2011, Orlando, Florida
A Broadband Multi-hop Network for Earth-Mars Communication using Multi-purpose Interplanetary Relay Satellites and Linear-Circular Commutating Chain Topology
Samudra E. Haque1 George Washington University, Washington, DC, 20052
Bandwidth utilization in the Mars exploration environment has been projected to increase past 1 Gbps duplex within the next decade. At present, all communication is routed through the Deep Space Network and is subject to the variable orbital geometry of Earth, Mars and the Sun. Data Communication speeds, between Earth and Mars, are neither satisfactory nor can they be utilized on a 24x7 basis, due in part to the lack of a space based telecommunication backbone. A holistic assessment of the merits of multi-hop communication in deep space was undertaken during 2009-2010, and a potentially robust new solution, employing a novel Linear-Circular Commutating Chain (LC3) architecture, developed for persistent, broadband connectivity between Earth and Mars. New classes of spacecraft suitable for use as Multi-purpose Interplanetary Relay (MIR) satellites in helio- centric orbit are outlined. Preliminary communication link budget and orbital analysis of a two-constellation MIR satellite network is presented, consisting of a linear chain of satellites ( group, 36 nodes) following Mars, and a circular chain of satellites located inside of Earth’s orbit ( group, 292 nodes). Potential orbital tracks are presented for network (365 nodes, including spares) supporting 1 Gbps end-to-end transmission with intermediate switching/trunking facilities, that should be able to be constructed by 2020 and serviced in deep space, using readily available technology practices. The proposed network avoids occultation problems caused by Earth-Sun-Mars geometry, provides redundant capability, and if desired, can be extended with very high capacity Optical links in place of, or in addition to, the RF links. A preliminary space mission concept summary is also included.
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