Cocentered Orthogonal Loop and Dipole Antenna for Borehole Radar
نویسندگان
چکیده
In this paper, we will introduce a cocentered orthogonal loop and dipole antenna (COLD) to a borehole radar system. With the cocentered orthogonal loop and dipole antenna, we could obtain additional information on polarization state of arrival waves in the borehole radar using * optical modulators. We set the proposed antenna in a borehole actually, and made electromagnetic waves with known polarization state incident on the antenna. In this experiment, we found that output signals from the antenna correspond to the polarization state. In order to investigate validity of the antenna in actual measurement, we conducted a field experiments in granite with antenna. Synthetic aperture processed data showed that the two antennas gave completely different images in anisotropic media.
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