Symposium on Radar and Radiometric Observations of Venus during the 1962 Conjunction: Further Venus radar depolarization experiments
The antenna feed system employed during the 1962 Jet Propulsion Laboratory Venus radar experiment permitted the remote automatic selection of the sense of circularity independently for both transmitting and receiving. During most of the experiment, right-handed circularly polarized energy was transmitted and left-handed circularly polarized energy was received. (Specular reflection reverses the sense of cir- cularly polarized energy.) Several times during the experiment, however, right-handed circularly polarized energy was both transmitted and received. The depolarized component was found to be approximately 11.5 dB below the matched component. An integrated spectrum of the depolarized component was compared with the matched return. Although the spectrum is extremely noisy, it appears that the depolarized echo- scattering law lies somewhere between Lambert and Lommel-Seeliger scattering, characteristic of a rough surface. The matched component has a very pronounced specular spike, which would be expected from a smooth reflector.