Domain decomposition FDTD algorithm combined with numerical TL calibration technique and its application in parameter extraction of substrate integrated circuits

An efficient hybrid algorithm, known as the "domain decomposition finite-difference time-domain" (DD-FDTD) method combined with a numerical thru-line (TL) calibration technique, is proposed and developed for the accurate parameter extraction of microwave circuits and structures. By means of a TL technique, the developed FDTD algorithm not only greatly increases the accuracy of numerical simulations but it also saves computation time and memory space. Moreover, the hybrid algorithm can be used for the parameter extraction of arbitrary complex circuits and structures, such as substrate integrated circuits (SICs). The SICs that are studied in this work are based on substrate integrated waveguides, which are useful for the design of millimeter-wave planar circuits such as filters, resonators, and antennas. On the basis of the characteristic features of numerical calibration process, an idea of domain decomposition is introduced to simplify the procedure of programming and simulation and to increase the simulation's reliability. Simulation and measurement results have verified this hybrid algorithm.