COM DEV Europe’s Scatterometer On Board Just-Launched MetOp Satellite

[SatNews] …provide high precision measurements of wind velocity over the world’s oceans using real aperture radar…The high power radar signal is continually switched to six antennas for transmission to the ocean surface.

COM DEV Europe Ltd, a subsidiary of space hardware manufacturer COM DEV International (TSX: CDV) welcomed the successful launch of Europe’s second polar-orbiting weather satellite, MetOp, from the Baikonur Cosmodrome, in Kazakhstan, atop a Russian Soyuz launcher.  One of the core instruments on the spacecraft called ASCAT features critical technologies developed at COM DEV’s Aylesbury facility.

ASCAT is an Advanced Scatterometer instrument operating in the C-band (5.255 GHz). Flying in a polar orbit at an altitude of 800km on board the MetOp series of satellites, its primary function is to provide high precision measurements of wind velocity over the world’s oceans using real aperture radar. The high power radar signal is continually switched to six antennas for transmission to the ocean surface. The back-scattered signal (echo) from the wind-roughened surface is then received and analysed and the wind speed and direction can subsequently be derived. The polar orbit enables the instrument to build a global picture of wind conditions across a 550 km-wide swath as the Earth rotates underneath it during its 100 minute orbit over the North and South poles.

COM DEV Europe designed and manufactured the Scatterometer Front End (SFE) electronics for the ASCAT instrument. The principal element of the SFE was a C-band switch matrix, using a ring of eight ferrite switches to route a high power RF signal (82W CW) from a HPA to one of six antennas, and to route the receive signal from the specified antenna to the receive channel. Additional ferrite switches were provided for receiver protection. Ferrite was the ideal switch technology for this application combining high power handling, low insertion loss, and the ability to be switched at the required pulse repetition frequency of 300Hz, resulting in a total of over 10,000 million switch operations during the mission lifetime. COM DEV Europe also provided calibration paths (including injected signal and power detectors), a harmonic filter for the transmit signal, and an RFC filter and LNAs for the receive signal.