Dipole Antenna Reception of Transient Electromagnetic Fields Refracted from a Dipole Antenna Buried in a Lossy Half-Space

Yiwei HE  Masahiko MARUYAMA  Toru UNO  Saburo ADACHI  Takunori MASHIKO  

IEICE TRANSACTIONS on Electronics   Vol.E74-C   No.9   pp.2870-2876
Publication Date: 1991/09/25
Online ISSN: 
Print ISSN: 0916-8516
Type of Manuscript: Special Section PAPER (Special Issue on OFSET '90)
Category: Transient Field

Full Text: PDF>>
Buy this Article

The characteristics of transient electromagnetic responses between two dipole antennas are investigated theoretically and experimentally for the case where one dipole antenna is located above an interface of a lossy ground half-space and another is buried underground. First, an asymptotic expression for the refracted electric fields is derived based on the saddle point method when a horizontal dipole is buried in the lossy half-space. A suitable saddle point which differs from the conventional one is selected for evaluation when the observation point is located far enough away from the buried antenna. The resultant formula indicates that the refracted electric fields can be interpreted by the sum of two waves. When the observation point is very close to the interface, one of which is a direct wave which propagates from the buried antenna toward the interface point just beneath the observation point and the other a lateral wave which propagates from the buried antenna to the interface with an angle of total reflection and then propagates along the interface. Next, the transient reception voltages of the antenna over the ground surface are measured. It is shown that the experimental results agree very well with the theoretical results, confirming the validity of the theory.