Abstract: The electric-field equation（EFIE） can formulate arbitrary structure, EFIE leads to inefficient solution due to the ill-conditioning of the matrix equations. The magnetic field integral equation（ MFIE ） is employed to formulate composite geometries with colsed conducting surfaces and the convergence is good. The hybrid MFIE-EFIE techniques introduced in this paper, FEKO based on the application of the MFIE on the colsed surfaces and EFIE on the open surfaces, good convergence is achieved.