Effect of porous structure on the phase change of SHF electromagnetic waves
Abstract
Electromagnetic microwaves are an effective means of nondestructive testing of components made from dielectric materials. Porous media - which include most dielectrics - exhibit a marked effect due to interference associated with multiple reflection from pores, even when the size of pores is substantially smaller than the wavelength. A formula is obtained for evaluating the effect of a porous medium on the phase shift of a traveling electromagnetic wave in the microwave range. The formula is based on the physical pattern of interference between waves undergoing multiple reflection at the interfaces with the inhomogeneities. Experimental results are found to be in good agreement with theory.
- Publication:
-
Defektoskopiia
- Pub Date:
- September 1974
- Bibcode:
- 1974Defek..10..103S
- Keywords:
-
- Dielectrics;
- Microwave Transmission;
- Nondestructive Tests;
- Phase Shift;
- Porous Materials;
- Microwave Probes;
- Permittivity;
- Superhigh Frequencies;
- Wave Reflection;
- Physics (General)