The scattered far field from a perfectly conducting circular cylinder with a fin is calculated using a hybrid method which combines Physical Optical（PO）

FOCK theory

Physical Theory of Diffraction（PTD）

Geomtrical Theory of Diffraction（GTD） with Moment of method（MM） . Results are compared to those of MM and those of Micheali’s theoretical calculation and measured data

and quite good agreement is obtained. In comparison to Micheali’s theoretical analysis

the hybrid method is valid for any magnitudes of cylinder radius and the fin width

and for any incident angle.