Patent ID: 6604225
Filing Date: 2003-08-05
Classification: G01R,G06F

Abstract:
A computer implemented method of calculating an electromagnetic field intensity, comprising:a) inputting geometric data of an electric circuit device located outside of the computer; b) calculating, from the geometric data, approximation coefficients for each of approximate equations that respectively yield approximate values of electromagnetic characteristic values, between a plurality of elements constituting the electric circuit device and of the elements themselves, at an arbitrary frequency; c) calculating approximate values of the electromagnetic characteristic values between the elements and of the elements themselves at a designated frequency in accordance with the approximate equations having the approximation coefficients calculated in b), making it possible to evaluate the electromagnetic field intensity for the designated frequency, each of said approximation equations including a real part which is a sum of terms with frequencies raised to an even numbered power and an imaginary part which is a sum of terms with frequencies raised to an odd numbered power; d) calculating an electric current flowing on each element by solving simultaneous equations obtained by substituting the approximate values of the electromagnetic characteristic values calculated in c) into equations respectively describing boundary conditions for the elements; e) calculating the electromagnetic field intensity for the designated frequency from the electric currents respectively flowing on the elements calculated in d); and determining, using the calculating in e), proper shielding required for the electric circuit device, wherein the b) includes: i) calculating the electromagnetic characteristic values between the elements and of the elements themselves from geometric data of the elements at each of a plurality of sample frequencies: and ii) calculating the approximation coefficients by solving simultaneous equations obtained by substituting the electromagnetic characteristic values calculated at the plurality or sample frequencies into each of the approximate equations.