Finite Difference Method for Transmission Line and Waveguide Problems

In the present work we have developed the numerical solutions for various partial differential equations such as electromagnetic problems using finite difference method. The electromagnetic problems under consideration are (a) Transmission lines and (b) waveguide. In case of transmission lines problem the governing equation is Laplace equation. We have computed the characteristic impedance of shielded double micro-strip transmission lines. The computed values of the characteristic impedance are comparable with the theoretical values. In the waveguide problem where the governing equation is Helmholtz equation, we have computed the cut off wave number kc for the TM modes in the rectangular waveguide. The cut off wave number kc for the lowest TM modes obtained were compared with theoretical values, and they were found to be satisfactory. All the implementations have done by using Matlab.