Craig Ian Underwood

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In this paper we propose two improvements to standard JPEG coding that can improve the compression ratio achieved for compressing remote sensing images obtained by sensors on-board micro-satellites by more than 39-60%. The first improvement consists in using a quantisation table that has been shown experimentally to be more appropriate for remote sensing(More)
In 1994, a collaborative programme was set up between the University of Surrey and the Chilean Air Force to design and build a low-cost 50 kg microsatellite with instrumentation capable of monitoring the distribution and concentration of stratospheric ozone, particularly over Chilean territory. This resulted in the joint design and development of the(More)
The bistatic radar technique of Global Navigation Satellite System-Reflectometry (GNSS-R) is capable of measuring wind and wave parameters using a passive instrument on-board a small satellite platform. In this paper, data from the Space GNSS Receiver-Remote Sensing Instrument (SGR-ReSI) experiment on-board TechDemoSat (TDS-1) are analyzed to perform(More)
In the framework of the European Copernicus programme, the European Space Agency (ESA) has launched the Sentinel-2 (S2) Earth Observation (EO) mission which provides optical high spatial -resolution imagery over land and coastal areas. As part of this mission, a tool (named S2-RUT, from Sentinel-2 Radiometric Uncertainty Tool) estimates the radiometric(More)
The upper atmosphere is a transition region between the neutron-dominated aviation environment and satellite environment where primary protons and ions dominate. We report high altitude balloon measurements and model results characterising this radiation environment for single event effects (SEE) in avionics. Our data, from the RaySure solid-state radiation(More)
The outer electron belt poses a significant radiation hazard to spacecraft due to internal charging and dose effects. We present a new user-friendly model to characterise the worst-case environment built on data from the Giove-A spacecraft. We use instrument data based on a novel technique of direct charging current measurements, uncontaminated by protons(More)
The ability to autonomously determine the position and attitude of a swarm of satellites is a promising way of assembling Intelligent Self-powered Modules (ISMs) in orbit. This self assembly is guided through simple actuators and sensors and requires fewer resources. A vision based system is used to determine the pose of ISMs attempting docking, through two(More)