Virtual ray-tracing in composite wedge and constructing the diffraction coefficients

Abstract

To correct the error posed in the PO(physical optics) diffraction coefficients of a composite wedge composed of perfect conductor and lossless dielectric, virtual rays in the complementary region are traced until all of the virtual rays should be located only in the complementary region. The one-to-one correspondence between geometrical rays and cotangent functions provides the extended diffraction coefficients routinely if those angular period is adjusted to satisfy the edge condition at the tip of the composite wedge. It is assured that the extended diffraction coefficients satisfy the null-field condition in the complementary regions quite well.