Based on the effective dipole model of conducting particles impinged by high frequency electromagnetic wave, the improved Bruggeman formulas included the renormalized permittivity and renormalized permeability that take into account effective of surface retardation are derived by effective media theory （EMT）. Numerical results exhibit the properties of effective electromagnetic parameters of mental particle-dielectric composites with frequency. For nonmagnetic mental particle composites, the high imaginary parts of effective permittivity reve...
