A multiple-GPR detection system was simulated. The main advantage of such a system was that it saves time by detecting both the transverse and the longitudinal positions of the target by a B-scan measurement, whereas the same detection can be achieved by a C-scan with a single-GPR system. Finite-domain time-difference (FDTD) method was employed to perform the simulations, in which the ground was homogeneous and the target was perfectly conducting.