EO·Atlas
TechDemoSat-1 (TDS-1)
Compiled from public sources on 2026-06-11. Not independently verified by Surrey Satellite Technology Ltd.
Work at Surrey Satellite Technology Ltd? This page is unclaimed. Claim it free to keep it accurate and add your links. What operators can do →
UK technology demonstration satellite launched July 2014 by SSTL; carried SGR-ReSI GNSS-R instrument from Surrey Space Centre; first spaceborne demonstration of GNSS-R for ocean wind speed retrieval at scale.
TechDemoSat-1 (TDS-1) was a UK technology demonstration satellite built and operated by Surrey Satellite Technology Ltd (SSTL), launched on 8 July 2014 into a sun-synchronous orbit at 635 km altitude. The mission ended in May 2019 following deployment of its de-orbit sail.[1][2]
The primary instrument relevant to Earth observation was the SGR-ReSI (Space GNSS Receiver Remote Sensing Instrument), developed by Surrey Space Centre. SGR-ReSI was a 24-channel GNSS reflectometry receiver capable of processing GPS L1 signals and designed for Galileo and GLONASS compatibility, with dual FPGAs enabling real-time delay-Doppler map (DDM) generation. TechDemoSat-1 demonstrated spaceborne GNSS-R ocean surface wind speed retrieval from a dedicated GNSS reflectometry instrument.[3][1]
The methods and hardware validated on TechDemoSat-1 directly informed the design of the CYGNSS constellation (launched 2016) and the SGR-ReSI-Z receiver carried by the HydroGNSS Scout mission (launched 2025). TDS-1 carried a total of fifteen technology demonstration payloads across communications, propulsion, and remote sensing domains.[2]
- [1]TechDemoSat-1 mission overview, eoPortalagency doc2026-06-11
- [2]TechDemoSat-1, SSTL space portfoliooperator marketing2026-06-11
- [3]Spaceborne GNSS-Reflectometry on TechDemoSat-1, Unwin et al. JSTARS 2016peer reviewed2026-06-11