Volume 1, 2022
Overview of the Near-Ground Propagation Mechanisms in Wireless Communication: Is the Norton Surface Wave Significant?
Krzysztof A. Michalski and Juan R. Mosig
Abstract: In this paper we re-examine the solution of the century-old Sommerfeld problem of a vertical Hertzian dipole radiating over planar ground, in the context of high-frequency applications, where the media losses are relatively small. To gain more insight into the near-ground wireless propagation mechanisms, we derive the asymptotic field of a dipole above a half-space by the modified saddle-point method carried out to the second order in the inverse radial distance, paying particular attention to the Norton surface wave and its significance in the total field of the dipole. We illustrate and validate the theoretical developments by numerical results involving various transmitter-receiver configurations of interest and different lower half-space media, including seawater and urban ground. We also briefly review the history of this problem and the most pertinent literature, addressing certain lingering controversies and correcting some recent misconceptions.