Whispering-gallery and Luneburg-lens effects in a beam-fed circularly layered dielectric cylinder

The whispering-gallery (WG) mode excitation and Luneburg (1941) lens (LL) effects are studied for a lossy circularly layered dielectric cylinder illuminated by a beam field. The latter is simulated by the complex source-point (CSP) beam. Exact series solution to the wave scattering problem is used to obtain the far-field patterns and directivity. The WG mode effect is shown to undermine the LL performance.