Empirical equations on electrical parameters of coupled microstrip lines for crosstalk estimation in printed circuit board

Empirical equations for the self and mutual capacitance and inductance (C/sub s/, C/sub m/, L/sub s/, L/sub m/) of coupled microstrip lines in a printed circuit board were derived from the numerical simulation results to reduce the computation time for crosstalk estimation. Comparison of the measured C/sub s/, C/sub m/, L/sub s/ and L/sub m/ values with the derived empirical equations showed good agreements. Also in the near-end and far-end crosstalks, good agreements were obtained between measurements and the derived empirical equations. Microstrip lines embedded in the homogeneous dielectric material as well as those in the inhomogeneous medium with one side exposed to air were considered in this work. Based on the derived empirical equations, a design guide on the spacing between microstrip lines was established.