Low-Frequency Model for Rectangular Semi-Anechoic Chambers

An efficient and accurate method to compute the electromagnetic field inside a rectangular semi-anechoic chamber from 30 to 100 MHz is provided. A modal analysis method is used to develop the homogeneous and inhomogeneous solution. They are then combined with a generalized circuital analysis to take into account the effect of the several layers of ferrite and dielectrics on the walls. Several numerical results of the normalized site attenuation (NSA) of a semi-anechoic chamber are provided and compared with measurements, showing a very good agreement.