Abstract: The ongoing evolution in constellation/formation of CubeSats along with steadily increasing number of satellites deployed in Lower Earth Orbit (LEO), demands a generic reconfigurable multimode communication platforms. As the number of satellites increase, the existing protocols combined with the trend to build one control station per CubeSat become a bottle neck for existing communication methods to support data volumes from these spacecraft at any given time.
This paper explores the Software Defined Radio (SDR) architecture for the purposes of supporting multiple-signals from multiple-satellites, deploying mobile and/or distributed ground station nodes to increase the access time of the spacecraft and enabling a future SDR for Distributed Satellite Systems (DSS).
Performance results of differing software transceiver blocks and the decoding success rates are analysed for varied symbol rates over different cores to inform on bottlenecks for Field Programmable Gate Array (FPGA) acceleration. Further, an embedded system architecture is proposed based on these results favouring the ground station which supports the transition from single satellite communication to multi-satellite communications.
Radio amateurs James Cutler KF6RFX, Andrew Mitchell KD8RCO and K. Scott Tripp KD8IPK are involved in developing the Michigan Multipurpose Minisatellite (MCubed-2) at the University of Michigan.
The mission objectives for the MCubed-2 are to capture mid-resolution images of the Earth from Low Earth Orbit, perform a technology demonstration for a novel new Field Programmable Gate Array (FPGA), and train the next generation of Aerospace Engineers.
Testing the FPGA on a CubeSat platform will provide valuable information as to how it survives Low Earth Orbit and how well it operates when processing real image data.
M-Cubed implements a 3 mega-pixel CMOS camera that will transfer the image to the FPGA upon request. MCubed-2 is also an educational project for Engineering students at the University of Michigan. M-Cubed provides hands-on experience for students who would not otherwise have the opportunity to build flight hardware for a space mission.
The training these students gain by working on this project will better prepare them for work in the Aerospace industry. MCubed-2 is a 1U CubeSat and the group is proposing to use a 1 watt output simplex transceiver on UHF with 9k6 telemetry.
It is planned to launch from Vandenberg into a 770 km by 460 km 123 degree orbit with these spacecraft: Medgar Evers – CUNYSat-1 Cal Poly – IPEX: MSU – Firebird: UH – H-2: Kentucky Space – KySat-2: SLU – Argus: LLNL – Udjat: SMDC – TacSat-6, SNaP-1/2/3, SMDC ONE 2.3/2.4 Aerospace Corp. – AeroCube-5a/5b/6 AFIT – ALICE: GSFC/Siena College – Firefly: USC – MaVEx: USU – STACEM: