In this paper, a wide band antenna is proposed for ground-penetrating radar (GPR) system. This antenna consists of dipole antenna housed in a rectangular conducting reflector whose inner walls are coated by an absorbing material. The coating is composed of a number of layers with a conductivity profile designed to achieve the minimum voltage standing wave ratio (VSWR) of the dipole antenna over the frequency band of operation. The antenna impedance and VSWR are calculated using the finite-difference time-domain (FDTD) method. The antenna impedance and VSWR are presented over a wide-band of frequency. The capability of buried target detection by the proposed antenna is examined by investigating the coupling between the transmitting and receiving antennas in the presence and absence of buried targets. The operating bandwidth of the antenna is shown to be about 50%. The effect of the ground soil on the antenna characteristics is studied when the GPR system is placed at different heights above such a soil. The GPR system with the proposed antenna is shown to be capable of detecting the existence of buried targets.