Radiation of a Horizontal Dipole in the Presence of a Three-Layered Region and Microstrip Antenna
Yi Hui Xu
In this paper, we study in detail both the trapped surface wave and lateral wave excited by a dipole antenna parallel to the plane boundaries of a three-layered region in spherical coordinate. An approximate formula is obtained for the solution of the electrictype pole equation when a condition is satisfied by √k21-k20l≤0.6. Similarly, an approximate formula is obtained for the solution of the magnetic-type pole equation when a condition is satisfied by √ k21-k20l-π/2≤1. Furthermore, because of its useful applications in microstrip antenna, the radiation patterns of a patch antenna with specific current distributions are treated specifically. Analysis and computations are carried out in several typical cases. It is seen that, for the component E0Θ, the total field is determined primarily by the trapped surface wave of electric type, and, for the component E0Φ, the total field is determined primarily by the trapped surface wave of magnetic type.