1：Experimental Design and Method Selection:

The study uses a numerical approach based on the Boundary Element Method (BEM) to solve the space-time Hallen integral equation for the current distribution on an equivalent dipole antenna. The influence of the air-earth interface is modeled using a simplified transmission coefficient from Modified Image Theory (MIT).

2：Sample Selection and Data Sources:

Two equivalent dipole antennas are modeled based on commercial GPR antennas (GSSI Model 3101D and Model 3100), with specified dimensions and excitation by a Gaussian pulse voltage source. The lossy medium has parameters of relative permittivity εr=10 and conductivities σ1=1 mS/m and σ2=10 mS/m.

3：List of Experimental Equipment and Materials:

No physical equipment is used; the study is computational, involving numerical simulations.

4：Experimental Procedures and Operational Workflow:

The Hallen equation is solved numerically using the Galerkin-Bubnov variant of the Indirect Boundary Element Method (GB-IBEM). The transmitted electric field is calculated along an observation line at a depth of

5：5 m using integral relations. Data Analysis Methods:

The results are analyzed to observe the behavior of the electric field amplitude over time and along the observation line, with comparisons for different antenna types and medium conductivities.