Spaceborne Fiber Optic Data Bus (SFODB)

Spaceborne Fiber Optic Data Bus (SFODB) is an IEEE 1393 compliant, gigabit per second, fiber optic network specifically designed to support the real-time, on-board data handling requirements of remote sensing spacecraft. The network is fault tolerant, highly reliable, and capable of withstanding the rigors of launch and the harsh space environment. SFODB achieves this operational and environmental performance while maintaining the small size, light weight, and low power necessary for spaceborne applications. On December 9, 1998, SFODB was successfully demonstrated at NASA’s Goddard Space Flight Center (GSFC). INTRODUCTION The SFODB technology was jointly funded by the Department of Defense (DoD) and NASA SFODB and scheduled for integration on NASA’s Earth Orbiter 1 (EO-1) satellite. The Science Advisory Team chose SFODB for its design flexibility and widespread applicability to future Earth Science missions. The Spaceborne Fiber Optic Data Bus (SFODB) Technology was selected by the New Millenium Program/Integrated Product Development Teams as a high payoff, revolutionary technology suitable for flight validation upon the Earth Orbiter-1 Mission. For this mission, science users rated SFODB highest among all cross cutting spacecraft technologies. SFODB addresses the prevalent need for a high data rate, standardized “plug and play”, low power, small footprint, science instrument data interface. Such an interface is required for enabling and reducing the cost of NASA’s future Earth and Space Science Missions. NASA’s New Millennium Program leveraged off of DoD’s previous SFODB investment to flight validate and reduce non-recurring engineering for future hyperspectral imaging and other high rate spacecraft applications. In July 1998, due to primarily sensor cost, schedule, and spacecraft accommodation issues, SFODB was demanifested from the EO-1 mission. However, SFODB ground support equipment was developed with flight SFODB components and demonstrated at NASA’s Goddard Space Flight Center (GSFC) on December 9, 1998. Teamwork was essential for SFODB’s development. The SFODB project includes: joint DoD/NASA funding and technical support; joint TRW/Honeywell internal research and development to fabricate the radiationhardened component technologies; Orlando & Associates, Inc.’s oversight and IEEE 1393 compliance; Optical Networks’ and the University of Arkansas’ high speed optical transceivers; Broadband Communications Products demonstration and development of a low cost development system; and Litton Amecom’s commercialization of flight components. Full SFODB functionality was demonstrated by a team of BCP, OAI, and TRW engineers. Here, we present SFODB’s capabilities, an EO-1 example application, and the demonstrated results. TECHNOLOGY OVERVIEW SFODB is a revolutionary, high-speed spacecraft bus architecture based upon the commercial, Asynchronous Transfer Mode (ATM) telecommunications standard. The highly reliable, deterministic network can simultaneously support command, telemetry, and multiple high bandwidth instruments over its fiber optic bus. SFODB’s one gigabit per second data transfer rate represents a thousand-fold data rate increase over the flight proven SAE 1773 fiber optic protocol. The IEEE 1393 SFODB implements a redundant, cross strapped, ring-based architecture which includes one controller node and up to 127 transmit/receive nodes, as shown in Figure 1 below. Figure 1. SFODB Fiber Optic Network SFODB’s low mass, low power, and reliable, high speed data transfer rate make it well-suited for hyperspectral imaging and other high speed applications. SFODB was designed to support bit error rates less than 10 per node for non-solar flare environments and 10 per node during the maximum solar flare. Its commercial, software configurable, ATM based protocol provides users extraordinary flexibility when designing their data handling architectures. Its ATM compatibility allows the spacecraft to bypass the traditional groundstation and route data directly to the user. The fiber optic cable contains 100/140 micron, multimode graded index fiber. SFODB’s standard, plug and play interface attributes combine to significantly reduce spacecraft development Report Documentation Page Form Approved