A grooved-dielectric flat radome panel is analyzed in terms of an arbitrary direction of incidence on

planar slabs each of which is dielectrically anisotropic, homogeneous, and lossless. Using this model for the grooved panel, transmission coefficients of 90 percent or greater over a 10:1 frequency band and over

to

incidence angle are predicted and demonstrated experimentally. Measurements are presented on two panels from 3 to 35 GHz.