Accurate determination of frequency dependent three element equivalent circuit for symmetric step microstrip discontinuity

A three element frequency dependent equivalent circuit which characterises a symmetric step microstrip discontinuity is determined using the method of lines. This method was applied so as to exploit to the full the processing capabilities of the available Cyber 205 computer, and to obtain results with the highest possible accuracy at frequencies in the range 4-16 GHz. Numerical values of scattering parameters are given for three geometries.