• Alleman, T. J., C. P. Cameron, and H. D. Mac Lean (1993), PEMSS response of rock tunnels to “in-axis” and other non-perpendicular antennae orientations, paper presented at 4th Tunnel Detection Symposium on Subsurface Exploration Technology, Colo. School of Mines, Golden, Colo.
  • Berenger, J. P. (1994), A perfectly matched layer for the absorption of electromagnetic waves, J. Comput. Phys., 114, 185200, doi:10.1006/jcph.1994.1159.
  • Duff, B. M., and B. J. Zook (1993), Time-frequency representations applied to analysis of hole-to-hole electromagnetic data, paper presented at 4th Tunnel Detection Symposium on Subsurface Exploration Technology, Colo. School of Mines, Golden, Colo.
  • Ellis, G. A., and I. C. Peden (1997), Cross-borehole sensing: Identification and localization of underground tunnels in the presence of a horizontal stratification, IEEE Trans. Geosci. Remote Sens., 35(3), 756761, doi:10.1109/36.581997.
  • Jung, J. H., and S. Y. Kim (2007), Measured dielectric properties of borehole cores using an open-ended coaxial probe, paper presented at IEICE 9th Workshop on Subsurface Electromagnetic Measurement, Inst. of Electon., Inf. and Commun. Eng., Seoul.
  • Jurgens, T. G., A. Taflove, K. Umashankar, and T. G. Moore (1992), Finite-difference time-domain modeling of curved surfaces, IEEE Trans. Antennas Propag., 40(4), 357366, doi:10.1109/8.138836.
  • Kelly, R. J., M. G. Biggs, H. Howard, G. A. Drutch, and J. A. Winter (1993), Pulse time of arrival detection apparatus for precision distance measuring equipment applications, Patent WO/1993/03398, World Intellect. Prop. Org., Geneva, Switzerland.
  • Kim, S. W., and S. Y. Kim (2000), Fully three-dimensional simulator for pulse borehole radar using the hybrid FDTD/PSTD, Proc. SPIE, 4129, 524527, doi:10.1117/12.390656.
  • Kim, S. W., and S. Y. Kim (2010), Analysis of cross-borehole pulse radar signatures measured at various tunnel angles, Explor. Geophys., 41, 96101, doi:10.1071/EG09048.
  • Kim, S. Y., and J. W. Ra (1993), The role of cross borehole radar in the discovery of forth tunnel at Korea DMZ, paper presented at 4th Tunnel Detection Symposium on Subsurface Exploration Technology, Colo. School of Mines, Golden, Colo.
  • Kim, S. W., S. Y. Hyun, J. H. Lee, S. Y. Lee, J. H. Cho, K. T. Oh, and S. Y. Kim (2007), The development of a pulse borehole radar system for underground cavity detection, IEICE Tech. Rep., 107, 9397.
  • Kim, S. W., S. Y. Kim, and S. Nam (2010), Estimation of the penetration angle of a man-made tunnel using time of arrival measured by short-pulse cross-borehole radar, Geophysics, 75(3), J11J18, doi:10.1190/1.3374356.
  • Lee, T. K., S. O. Park, S. Y. Kim, and J. W. Ra (1989), Near-field diffraction pattern by an underground void of circular cylinder, Microwave Opt. Technol. Lett., 2(5), 179183, doi:10.1002/mop.4650020511.
  • Luebbers, R., F. P. Hunsberger, K. S. Kunz, R. B. Standler, and M. Schneider (1990), A frequency-dependent finite-difference time-domain formulation for dispersive media, IEEE Trans. Electromagn. Compat., 32(3), 222227, doi:10.1109/15.57116.
  • Lytle, R. J., E. F. Laine, D. L. Lager, and D. T. Davis (1979), Cross-borehole electromagnetic probing to locate high-contrast anomalies, Geophysics, 44(10), 16671676, doi:10.1190/1.1440929.
  • Moran, M. L., and R. J. Greenfield (1993), Radar signature of a 2.5-D tunnel, Geophysics, 58(11), 15731587, doi:10.1190/1.1443373.
  • Olhoeft, G. R. (1988), Interpretation of hole-to-hole radar measurements, paper presented at 3rd Symposium on Tunnel Detection, Colo. School of Mines, Golden, Colo.
  • Peden, I. C., R. Kipp, and J. Allestad (1992), A scale-model study of down hole VHF dipole arrays with application to subsurface exploration, IEEE Trans. Geosci. Remote Sens., 30(5), 885891, doi:10.1109/36.175322.
  • Sato, M., and X. Feng (2005), GPR migration algorithm for landmines buried in inhomogeneous soil, in IEEE International Symposium on Antennas and Propagation, vol. 1B, pp. 206209, IEEE, Washington, D. C., doi:10.1109/APS.2005.1551522.
  • Schneider, J., and I. C. Peden (1993), Detection of tunnels in low loss media illuminated by a transient pulse, IEEE Trans. Geosci. Remote Sens., 31(2), 503506, doi:10.1109/36.214926.
  • Taflove, A., and S. C. Hagness (2005), Computational Electrodynamics: The Finite-Difference Time-Domain Method, Artech House, Norwood, Mass.
  • Takahashi, K., and M. Sato (2006), Parametric inversion technique for location of cylindrical structures by cross-hole measurements, IEEE Trans. Geosci. Remote Sens., 44(11), 33483355, doi:10.1109/TGRS.2006.879542.
  • Uno, T., Y. He, and S. Adachi (1997), Perfectly matched layer absorbing boundary condition for dispersive medium, IEEE Microwave Guided Wave Lett., 7(9), 264266, doi:10.1109/75.622532.
  • Watanabe, S. I., and M. Taki (1998), An improved FDTD model for the feeding gap of a thin-wire antenna, IEEE Microave. Guided Wave Lett., 8(4), 152154, doi:10.1109/75.663515.
  • Yee, K. S. (1966), Numerical solution of initial boundary value problems involving Maxwell's equations in isotropic media, IEEE Trans. Antennas Propag., 14, 302307, doi:10.1109/TAP.1966.1138693.
  • Zhou, H., and M. Sato (2004), Surface cavity imaging by cross borehole radar measurements, IEEE Trans. Geosci. Remote Sens., 42(2), 335341, doi:10.1109/TGRS.2003.817215.