According to  and , the transfer impedance and admittance of the shield can be expressed in the frequency domain as
At the frequencies of interest, the transfer impedance is much larger than the transfer admittance, and this is because the electric field shielding of the shield is much better than the magnetic field shielding, which means that the shield current is more important than the shield-to-ground voltage for the induced voltage of the load [R.
The SAE ARP 1705 transfer impedance test measures the electrical characteristics of the RF gasket material.
Figure 5 illustrates the relationship between the radiated and transfer impedance methods.
The intrinsic impedance and the surface transfer impedance become equal for material thicknesses greater than approximately three skin depths.
The SAE ARP 1705 transfer impedance measurement is performed using a coaxial fixture that allows placement of the sample between the inner and outer conductors of the coaxial fixture.
The resistive and inductive losses that make up the combination of transfer impedance plus any series contact impedances cause an RF voltage to be developed across the current conduction path.