A theory of radar reflection from the Moon and planets

Abstract

Huygens’ principle is used to derive relations between the surface statistics of a randomly irregular celestial radar target and the angular power spectrum and autocorrelation function of the reflected signal. The spatial correlation function of the signal observed by spaced receivers is also computed. From observed lunar signal fading data a crude pictorial representation of the small-scale structure of the moon's surface is constructed. The angular power spectrum is derived from the autocorrelation function of the signal fading, and the result is compared with the angular distribution measured directly by means of the pulse-delay technique.