Analysis of microstrip discontinuities using the finite difference time domain technique

The authors demonstrate the potential of the finite-difference time-domain technique for analyzing MMIC (monolithic microwave integrated circuit) structures of arbitrary complexity with moderate computational effort and for meeting the requirement for CAD (computer-aided design) tools capable of treating high-density MMICs. Results are presented for the propagation constant of a uniform microstrip, calculated using this method, which show excellent agreement with those obtained using the SDM (spectral domain method). Results are also presented for the parameters of structures containing a right-angle bend in microstrip and an abrupt termination in microstrip. The latter results are compared to those obtained by means of the SDM, and good agreement can be seen.<>