Telescopes of the radio astronomy service (RAS) are designed to achieve strong isolation from ambient radiation and have been placed in remote locations whenever possible, to enable detection of cosmic phenomena wherever they may occur on the sky (although typically above about 5° elevation). However, both cosmic and man-made signals which cross the main beam are received with very high gain, owing to the large apertures needed to detect weak cosmic signals. For man-made signals the combination of high receiving gain and high incident signal strength could suffice to permanently degrade the performance of a RAS receiver, or perhaps even destroy it. This Report describes the means by which the corresponding incident power flux-density (pfd) may be ascertained.
ITU-R REPORT RA.2188-2010 Referenced Document
ITU-R RA.1750 Mutual planning between the Earth exploration-satellite service (active) and the radio astronomy service in the 94 GHz and 130 GHz bands
ITU-R REPORT RA.2188-2010 history
2010ITU-R REPORT RA.2188-2010 Power flux-density and e.i.r.p. levels potentially damaging to radio astronomy receivers