PURPOSE: To realize efficient simulation of a wave emission from a pigtail part by using a moment method by a method wherein a model of a thick cylindrical coaxial cable connected to a pigtail lead wire in which a portion in the vicinity of the pigtail part is approximated with a polygon is formed.

CONSTITUTION: A cable pigtail part abstraction section 12 abstracts a pigtail part of an end of a coaxial cable. A model abstraction section 13 selects one of a strict modeling operation section 14 by a polygon model and a simple modeling operation section 15 by a wire for the modeling. The operation section 14 approximates a coaxial cable shield part near the end of the cable with a polygon cylinder on the basis of structure information of the pigtail part abstracted by the abstraction section 12 to form a model wherein the polygon part is connected to a housing of an electric circuitry device. Also, the operation section 15 forms a model wherein the coaxial cable shield part and a pigtail lead part are connected to each other with a wire wherein an electric current flows in a direction perpendicular to the coaxial cable. An electromagnetic field intensity calculation section 16 calculates an electromagnetic field intensity by utilizing a moment method.