Multi-Gbits/s network technology for space
Space Fibre has been developed for use with high data rate payloads, like synthetic aperture radars and hyperspectral optical imagers producing data at rates of several Gbits/s. This high-speed serial data link complements the capabilities of the widely used networking standard Space Wire. It provides more than 10 times wider bandwidth. The EU-funded project VHISSI (Very high speed serial interfaces) aimed to leverage research on Space Fibre to provide a complete solution for the on-board networks of Earth observation missions. To achieve this goal, the European microelectronics research community joined their efforts with large prime contractors and small and medium-sized enterprises. VHISSI's seven project partners were successful in developing an experimental chip implementing the Space Fibre serial communications protocol. It has been designed to integrate fault detection, isolation and recovery capabilities into the hardware. In addition, quality of service mechanisms allow the bandwidth of on-board communication networks to be specified. The VHISSI device provides a Space Fibre interface able to operate at the speeds of spaceflight-qualified field-programmable gate arrays while sustaining data transfer of 2 Gbits/s. Together with a router device to interconnect instruments, it is able to support multiplexing of packets containing instrument data, control or status information. A series of prototypes of the VHISSI chip were manufactured by a European foundry. Extensive testing has been carried out to cover all modes of operation. The results obtained at different temperatures and with different supply voltages have demonstrated its robustness. The interfaces of the chip performed at the speed they were expected to operate, suggesting that it fulfils the design goals. To date, the Space Fibre technology relied on United States-based providers for radiation-tolerant devices that could not, however, be used on European space missions. The VHISSI project has provided Europe with technology needed for spacecraft on-board data links and communications networks that will enable it to compete on the world market.
Keywords
Communication networks, Space Fibre, Space Wire, serial interfaces, Earth observation
