Scattering from a Rectangular Dielectric Cylinder by Mode Matching Technique

The propagated fields within and radiated fields outside a rectangular dielectric cylinder are represented as guided and radiation modes respectively. These fields of the cylinder are related with incident, backward scattered fields at x = 0 and transmitted fields at x = a by Mode Matching technique. The expressions for guided and radiation mode amplitudes are derived by applying the orthogonal property of the modes. The unknown functions (mode amplitudes) in each of these equations that are defining discrete functions of the guided modes field and angular spectrum for the radiation field are determined numerically. The powers due to discrete guided modes (even and odd) are calculated. The integrals related with the backward and forward scattered fields and the powers associated with them are approximately evaluated by the method of steepest descents.