Dear Sir,

the Definition of the shielding loss is D(dB) = 20 log ( Eo(f)/Ei(f) ).

Eo is field outside and E i is inside a material. If you have only a Absorption material ( not any reflections ) you can use S11 für E.

Yours Sincerely

F. Gräbner

I have a question.

Sir, is there any method or theoretical model to calculate the return loss or reflection loss from existing dielectric parameters, such as permittivity and permeability.

Article Er3+-substituted W-type barium ferrite: Preparation and elec...

Thanks Rafia Raees.