Backscattering Cross Sections of Circular Disks for Arbitrary Incidence

Publisher Website
Google Scholar
Abstract
The backscattering cross sections of perfectly conducting circular disks at arbitrary incidence for polarizations both parallel and perpendicular to the plane of incidence have been calculated from Meixner and Andrejewski's solution, for disk sizes in the range 0.94≤ka ≤9.45. These results are compared with measurements, and good agreement is obtained over dynamic ranges of up to 40 dB except for errors in several measured patterns at the lower signal levels in the case of perpendicular polarization. The present calculations enhance the value of the disk as a standard for scattering measurements and calculations. Cross sections for disks normal to the magnetic field of the incident wave are given and are found to be in good agreement with earlier measurements. The small-disk approximation of Bethe is quite accurate for ka<0.4. These results may be used to test the accuracy of the high-frequency approximation which involves a diffracted wave propagating along the edge of the disk.