Field to shielded cable coupling inside a reverberation chamber: numerical and experimental analysis

The paper considers the reverberation chamber method for the measurement of the shielding effectiveness (SE) of coaxial cables with braided shields. In particular, the voltage at the cable termination is numerically computed and compared to that measured in a real chamber. The chamber field is represented by a finite summation of random plane wave and a FDTD code is used to calculate the outer shield current induced by the chamber field. The knowledge of the current shield distribution allows the determination of the voltage at the termination of the cable internal circuit, after a proper numerical averaging to compare it with the average, over the stirrer rotation, measured voltage. The method is applied to a commercially available cable model RG58 and, using the nominal value for the transfer impedance of this cable type, gives results in satisfactory agreement with measurements.