Domain decomposition FDTD algorithm combining with numerical TL calibration technique for parameter extraction of substrate integrated circuits

The substrate integrated waveguide (SIW) is useful for the design of millimeter-wave planar circuits such as filters, resonators and antennas. In this paper, an efficient hybrid algorithm called the domain decomposition finite difference time domain (DD-FDTD) method combining with a new numerical through-line (TL) calibration technique, is proposed and developed for the accurate parameter extraction of substrate integrated circuits (SICs). By means of this calibration technique, the FDTD method can be used to extract the circuit parameters of planar SIC discontinuities. The use of the domain decomposition can largely simplify the procedure of programming and simulation, increase the reliability of simulation, and make the adoption of distributed computing more convenient. The introduction of the TL calibration technique not only makes it possible to use the FDTD method to extract the parameters of SICs, but also accurately obtain the unknown complex propagation constant of the SIW simultaneously. Simulation and measurement results have verified this hybrid algorithm.