Diffraction by a conducting half-plane with application to radar target shadowing

The field received at a moving radar which illuminates a far-field point target is derived for the two-dimensional case when the target is shadowed by a perfectly conducting half-plane. This problem arises in radar imaging and in certain calculations of radar cross-section. The derivation is based on an approximate analysis of line source diffraction by a conducting half-plane using antenna aperture analysis and image theory. The approximate solution is the same as that obtained by integral equation techniques and, in particular, leads to the exact (Sommerfeld) expression for plane wave incidence on the half-plane. Results from the radar solution quantify errors in estimating the dimensions of target features when the features are in the vicinity of shadow boundaries during the imaging process