Embedded Modulating Dipole Scattering for Near-Field Microwave Inspection of Concrete: Preliminary Investigation


Nondestructive evaluation of concrete structures is an important practical issue in the construction industry. Evaluation encompasses many issues including concrete constituent property, compressive strength and chloride contamination determination to name a few. To this end, a combination of modulated scattering technique and near-field microwave nondestructive evaluation technique, is used to determine its potential for evaluating dielectric properties of a hardened mortar specimen. This technique utilizes a small resonant PIN diode-loaded dipole scatterer embedded inside the mortar while using an open-ended rectangular waveguide probe operating at 7 GHz to detect this dipole which is modulated at low frequencies. The results of this preliminary experiment, and its future ramifications for nondestructive concrete inspection structures are provided in this paper.

Meeting Name

Subsurface Sensors and Applications (1999: Jul. 19-21, Denver, CO)


Electrical and Computer Engineering

Keywords and Phrases

Dielectric Properties; Diodes; Microwaves; Nondestructive Examination; Rectangular Waveguides; Scattering; Diode Loaded Dipole Scatterer; Embedded Modulating Dipole Scattering; Near Field Microwave Inspection; Open Ended Rectangular Waveguide Probe; Mortar

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Document Type

Article - Conference proceedings

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© 1999 SPIE--The International Society for Optical Engineering, All rights reserved.

Publication Date

01 Jul 1999