A Novel Approach for Modeling Diodes Without Reducing the Time Step in the FDTD Method

A novel technique is proposed to incorporate diodes into the finite-difference time-domain method. The equivalent circuit of the diode is combined with Yee´s time-stepping equations to update the fields by solving a quadratic equation, without using the time-consuming iterative method at each time step. Two types of diodes connected at the end of a microstrip transmission line are investigated to demonstrate the validity of this method. Stability of the proposed method is demonstrated numerically and the accuracy is verified by comparison with commercial software ADS.