Carrier-free GPR(Ground-penetrating Radar) is a near-ground-time-domain detecting system using nanosecond pulse, influenced by half-infinite lossy media interface, therefore the analysis of scattering features of the near ground time-domain antenna is extremely difficult. This paper designs a bow-tie antenna loaded with patch resistors. Results of FDTD (Finite-difference Time-domain) calculation show good fidelity of the wave, and exciting radiation features as well as fine effect of shielding. It can be widely used in GPR and other UWB (Ultra-wide-band) systems.