The satellite weighs about 140kg and is just about the size of a washing machine. The mini-satellite Proba-V is covered in solar cells and will be observing the vegetation on earth. Every other day, the environmental satellite will send pictures from a distance of about 820km. Rain forest destruction, pollution of the seas and soil erosion will be made visible by pictures taken in various spectral ranges.
Being more robust, more compact and lighter than traditional solutions, the new GaN technology promises to significantly improve communication electronics in space. “We expect signal strength and data transmission to improve five- or tenfold,” says Andrew Barnes, who is responsible for the project at ESA. Based on GaN high-electron-mobility transistors (HEMTs), the amplifier circuit operates in the 8–8.5GHz (X-band) frequency range for Proba-V’s communication system. Tesat-Spacecom GmbH of Backnang, Germany, in cooperation with SCHOTT Electronic Packaging, packaged the amplifier together with further components into a hermetically sealed housing suitable for operation in space. “We are eagerly awaiting the results of the first practical test in space,” says Barnes.