Diffraction Measurements at 1.25 Centimeters

Abstract

Measurements have been made, using an image plane technique, of microwave diffraction near obstacles whose characteristic dimension is comparable to a wavelength (1.2668 cm). Detector, obstacle, and source of radiation are mounted on one side of a horizontal 4‐ft by 6‐ft conducting plane, and the operator and all auxiliary apparatus are located on the other. Measured distributions of both the phase and amplitude of the electric field near long cylinders of brass and polystyrene were obtained, and for the conducting cylinders these are compared directly with the results of a suitably modified theory. The technique has been extended to diffraction by a semi‐infinite conducting plane screen, and it was found in this case that considerable error is introduced by the point source. With the substitution of a line source the measurements are again in close agreement with the theory.