Application of FDTD/Kirchhoff method for radiation pattern calculation

In this paper we describe a hybrid method to calculate radiation pattern for electromagnetic compatibility (EMC) and microwave antennas, which employs the finite difference in time domain (FDTD) algorithm and the Kirchhoff's integral as near-to-far-field transformation. The memory requirements of such a method are discussed and evaluated. A log-periodic dipole array (LPDA) antenna has been chosen as test case; the numerical simulation results are compared against experimental measurements, showing a good agreement.