Performant and Flexible On-Board Processing Modules Using Reconfigurable FPGAs

Current and future space missions demand sophisticated on-board data processing functionalities, while low resources consumption remains a constraint. Thus, in-flight reconfigurable architectures are mandatory. Using dynamically reconfigurable FPGAs allows enhancement of on-board processing with unprecedented levels of flexibility, enabling the adaptation of the system regarding functional and fault-tolerance requirements, subjects to change during mission lifetime. Different operational modes can be served, especially for sharing of complex algorithms on limited FPGA resources.

For instrument control and data processing of the PHI instrument on the Solar Orbiter mission (SO/PHI), we have partially adapted results of the ESA study for a Dynamically Reconfigurable Processing Module (DRPM) and implemented a flexible, in-flight reconfigurable, power efficient, and radiation tolerant processing module based on Xilinx Virtex-4 SRAM-based FPGAs. While these and the rad-hard Virtex-5 FPGAs have been used for many current space missions, they provide only insufficient logic resources and embedded memory for future usage. Instead, the Kintex Ultrascale XQRKU060 has become a state-of-the-art rad-tolerant FPGA implementation. As the Xilinx Zynq Ultrascale+ shows, integration of dedicated processors is presently used already for military and commercial space applications.

After having demonstrated the usage of in-flight reconfigurability for SRAM-based FPGAs on SO/PHI, we have developed a universal platform for high performance on-board data processing, based on cPCI Serial Space standard and state-of-the-art Xilinx Zynq Ultrascale+ MPSoC device on a single board (3U). The cPCI Serial Space standard guarantees the modular extensibility of the system. The board provides two banks of 64 Gibit DDR3-SDRAM memory and TMR NOR-Flash for configuration and SW code, together with various interfaces, like PCIe, SpaceWire, and Ethernet. Optionally, this could be expanded to control NAND-flash mass memory or implemented with an EV-MPSoC including video codec to enable compression and recording of data streams from video cameras.

This module is being used within the H2020 project S4Pro, which investigates how to combine state-of-the-art industrial computing technologies (namely Xilinx Zynq UltraScale+) and space qualified embedded computing platforms in order to optimize the data processing chain and support the next generation of data intensive missions. The approach targets not only the enhancement of technology transfer to nano- and small satellites, but also the enabling of institutional satellite missions that rely on operational tasks with very high bandwidth, processing, and storage requirements. Hence, the Zynq Ultrascale+ is used for on-board data elaboration, e.g. for SAR and multispectral imaging applications, due to its strong interfacing capabilities and integrated software processing units based on the ARM A53 core architecture.

Additionally, we are implementing a derivate with similar cPCI Serial Space interfaces using the Xilinx XKU060 (XQRKU060) FPGA. Especially for different types of reconfiguration and scrubbing, a system controller connector is available to connect a special reconfiguration engine. This can be used also to perform fault injection into the FPGA and thus exercise FDIR aspects. Based on this, we are involved in a design study for the Lagrange PMI instrument DPU as follow-on of SO/PHI. In the full paper, we will present more details of our modules and applications.