THE FOCUSABLE DARK-FIELD ANTENNA

The paper discusses the properties of focusable dark-held antennas wit h special reference to the observation of weak scatterers. In this for m of observation, one darkens the held at the focus of the signal sour ce in whose held the scatterer is observed. A comparison is made betwe en a method whereby a scattered signal is detected in the presence of a brightening signal and the separation of convolved signals by Oppenh eim's cepstrum analysis technique. The calculated results are presente d which make it possible to determine the possible degree of separatio n of the scattered and brightening signals with allowance for the acou stic waveguide mode dispersion.