DIY Aperture Arrays

© Centre for Space Research, Faculty of Natural Sciences, North-West University, South Africa

Armed with nothing more than a Gerber-file, a couple of low-noise amplifiers and a pair of running shoes, the recent visit by Paulus Kruger served as a refreshing reminder of the rapid prototyping capabilities of ASTRON's R&D department. Paulus is a senior lecturer with the Centre for Space Research at the Potchefstroom campus of North-West University, South Africa. Currently, he is working towards a DIY aperture array prototype to serve as an educational instrument within their department.

During his visit, Paulus was quick to identify the key figures needed within the Radio Group to bring one of his antenna prototypes to life. Once established, things went fast. Handing the Gerber-file over to the capable hands of Albert van Duin before coffee on Wednesday morning, the antenna with low-noise amplifier and ground plane stood ready for measurements (on top of the Vivaldi tile) within our THACO noise temperature measurement facility, 24 hours later. Ready at hand was our resident THACO expert, Martijn Brethouwer, ensuring the noise measurements were completed in time for Paulus to accompany a fellow South African on the 15 km leg of the Telescooploop in the afternoon.

As seen from the RFI-infused noise temperature measurement, DIY antennas do not necessarily imply compromised performance. This active antenna achieves a respectable noise temperature varying between 20 and 45 Kelvin. These results, produced in this time frame, is a clear demonstration of the solid foundation that has been laid by the aperture array development at ASTRON.