(color online) The far field monostatic co-polarized RCS of a PEC cylinder with 20 cm diameter and 30 cm length as a function of pitch angle. In (a), the observation is made at r ≫ r_ff. The RCS by MLFMM solution and the MPO solution are presented. In (b), the observation is made at r = 0.3 × r_ff. The RCS by measured data^[17] and the MPO solution are presented.