Transient Analysis of GPR Dipole Antenna Using Time Domain Energy Measures

Summary The paper deals with a direct time domain modelling of impulsively driven GPR dipole antenna above a homogeneous lossy half-space aiming to estimate the energy stored in the near field. The space-time dependent current is obtained by numerically solving the space-time Hallen integral equation and Pocklington equation via different approaches. The obtained results are compared to the results obtained via NEC and Inverse Fast Fourier Transform (IFFT). Provided the current is known one may calculate the charge distribution along the wire by using the one-dimensional version of the continuity equation. Knowing the space-time distribution of current and charge along the dipole antenna, time domain (TD) energy measures involving spatial integrals of squared values of transient current and charge, pertaining to the energy stored in the electric and magnetic field, respectively, of dipole antenna, are evaluated. Furthermore, total power measure defined as time derivative of the total energy measure is computed. Some illustrative computational examples for transient current, TD energy and power measures are given in the paper.