Title :
Borehole radar measurements
Author_Institution :
Dept. of Resource Eng., Tohoku Univ., Sendai, Japan
Abstract :
An analysis of transient responses between dipole antennas set in parallel boreholes is presented in order to obtain a basic understanding of the operation of borehole radars. The theoretical response was derived, and the results are found to agree well with measured data in a salt deposit. The guided wave induced on the cable and its effect on the antenna radiation pattern are considered. Although the direct wave from the transmitting antenna to the receiving antenna is always dominant, the induced guided wave along the coaxial cable suspending the receiving antenna is not negligibly small. Deformation of the radiation pattern is mainly caused by this guided wave, and it can be suppressed to some extent by loading ferrite cores on the cable.<>
Keywords :
geophysical prospecting; minerals; remote sensing by radar; transient response; antenna radiation pattern; borehole radars; dipole antennas; guided wave; parallel boreholes; salt deposit; transient responses; Antenna measurements; Antenna radiation patterns; Coaxial cables; Dipole antennas; Ferrites; Radar antennas; Radar measurements; Receiving antennas; Transient analysis; Transmitting antennas;
Conference_Titel :
Antennas and Propagation Society International Symposium, 1990. AP-S. Merging Technologies for the 90's. Digest.
Conference_Location :
Dallas, TX, USA
DOI :
10.1109/APS.1990.115289
