Vehicle radars equipped in modern self-driving cars can no longer use the 24 GHz band and will be switching to the 76−81 GHz band. Radio Astronomy detections of molecules in the interstellar medium are performed in the band with several first-class radio telescopes in Europe such as the 30-m radio telescope (IRAM Pico Veleta, Spain), the NOEMA interferometer (IRAM Plateau de Bure, France), the Onsala 20 m radio telescope (OSO, Sweden) and the 40m radio telescope (IGN-Yebes Observatory, Spain) in the 76−81 GHz range.
To understand the future impact of the adoption of this band by cars for radio astronomy, CRAF proposed an aggregate study for 10 radiotelescopes: NOEMA (France), SRT (Italy), Yebes (Spain), Best (Hungary), Onsala (Sweden), Effelsberg (Germany) Noto (Italy), Metsähovi (Finland), IRAM (Spain), and Medicina (Italy). Studies were conducted by simulating the car distribution around the radio telescope according to road classification given by Open Street Map. Furthermore, the car density was varied with the aim of emulating traffic fluctuations between day and night and throughout the year. The results show variations between locations because of the high dependence on terrain attenuation around the site. Excluding Effelsberg located in a valley well shielded by mountains, the rest of the studied radio telescopes will require at least an exclusion zone of a radius of 10 km. This study was proposed to CEPT-ECC project team SE24 at the September 2022 meeting.