AbstractSynthetic Aperture Radar (SAR) and super-resolution (fine spatial/spectral) optical remote sensing payloads, onboard Earth observation, science, and planetary missions generate a large amount of data at multi-gigabit per second. The output data rate from state-of-the-art SAR and imaging sensors can exceed 10Gbps, requiring a high bandwidth data handling system. Onboard electronics systems also face challenges due to constrained size, weight, power, cost and high-reliability requirements to sustain in the hostile space environment. Features like easy integration, testing and scalability are expected from an onboard system. These requirements can be met with high throughput, reliable data interfaces and an optimal architecture of the onboard data handling system.
SpaceFibre is a multi-Gbps onboard data link and network technology, developed by the University of Dundee for the European Space Agency (ESA). SpaceFibre fulfils these requirements through its high performance, inbuilt Quality-of-Service (QoS) and Fault Detection, Isolation, and Recovery (FDIR) capabilities. This research contributes towards a better understanding of spacecraft data handling systems and how SpaceFibre can meet satellite payload data system requirements.
There are a number of publications about the SpaceFibre standard, design, FPGA hardware implementation, and validation through ground check-out hardware. However, no studies of SpaceFibre have been carried out with an onboard compatible high data generating payload. This Ph.D. thesis contains an original contribution of designing an onboard compatible payload instrument (SpaceFibre camera) with SpaceFibre interconnection technology and a payload data handling network. The work includes analytical studies, software simulations, and hardware prototyping. A critical contribution is made towards the development of a payload data processor and SpaceFibre multilane interfaces on an FPGA to evaluate the novel data handling architecture, reliability, and SpaceFibre interface performance. The data system design of this research follows space hardware philosophies such as low power, miniaturisation, and the use of commercial-off-the-shelf for low cost and high reliability through redundancy. The Gbps SpaceFibre data interface and communication protocol are critically evaluated through specialised test equipment and software to define a test methodology for future SpaceFibre based systems. The modelling and analysis of the payload data system SpaceFibre network and its simulation on a network simulator (ns-3) is an original contribution to the knowledge in this field.
The second part of the thesis focuses on the analysis and identification of gap areas within SpaceFibre reliability and fault detection, isolation and recovery. The FDIR analysis of the protocol layers is carried out to identify any missing capabilities for availability and fault tolerance. The thesis researched how to enhance SpaceFibre fault tolerance by autonomously recovering any residual error reaching to the higher layer of the communication protocol. Recommendations have been made for higher layer reliable data transfer protocol to the existing SpaceFibre protocol and extension of configuration and status parameters of the protocol layers for non-recoverable errors recovery by the system FDIR of the spacecraft.
|Date of Award||2020|
|Supervisor||Iain Martin (Supervisor)|
- SpaceFibre Camera
- Spacecraft Data handling