A contribution to error decrease in plane wave scattering problems with triangular patch modeling

The problem of scattering of plane waves by perfectly conducting bodies using triangular patch modeling is considered. Analytical expressions for the vector coefficients of the matrix equation are presented, which should be used instead of the approximated ones, presented in the original formulation. It is seen that it is the variation of the incident wave phase on the triangle surface that contributes to the error. An analysis of the error is also done; it is null when the direction of incidence is normal to the triangle plane, but it can achieve a value of 20% for equilateral triangles when its side is X/4 and the direction of incidence is in its plane.