This paper presents an EM analysis of dispersions & discontinuities in a microstrip transmission lines, on semiconductor substrates for MMICs. MMICs are a circuit, where the complete passive and active circuit elements and interconnections are formed onto the plane of the substrate. A fast efficient less time consuming EM Simulator, which is based on MoMs, was used. Study based on simulations is for microstrip transmission line; right angle bend; single mitered, and double mitered discontinuities for semi-insulating GaAs substrates. A fullwave analysis of shielded microstrip two-port discontinuities & frequency-dependent scattering parameters, effective dielectric constant, VSWR for right angle bends & its compensations are simulated and analyzed. The CAD analyses for compensated and non-compensated discontinuities are simulated & compared in the frequency range 1GHz – 40GHz. The projected technique based on the simple taper on the wider line at a right angle bend to reduce the effects of the discontinuity.

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Microstrip lines Dispersions Discontinuities Scattering Parameters Effective Dielectric Constant and EM Simulations