A mixed technique of moment method（MoM）

conjugate gradient method（CGM） and fast Fourier transform（FFT） is presented to deal with the electromagnetic scattering of cylinders

which have arbitrary cross-sections and are composed of conductor or inhomogeneors dielectric. This methed is based on collocation technique in which eqnivalent current is considered as unknown function. CGM and FFT technique are used for reducing storage and CPU time

therefore electrically large cylinders of abitrary cross-sections and imhomogeneous permittivity can be handled simply and effectively. The numerical results for dielectric rectangular cylinder

circular and conducting cylinder are in agreement with classic results or results given in other papers.