A modelling approach to determining the effective working volume of a mode-stirred chamber

Achieving both high field strengths and field uniformity within resonant cavities is of increasing interest within the area of both civil and military EMC test and measurement. The mode-stirred chamber is just one of several methods currently employed to achieve these properties. This paper addresses the modelling approach to identifying the potential working volume in a mode-stirred chamber at frequencies well below, well above and at the nominal minimum working frequency. This is evaluated as a function of the peak field magnitude and stirrer rotation, and determines the level of dependence of the fields on both the stirrer geometry and location. The method is enhanced by the ability to visualise the field at any position P in the cavity for all instants of time over an entire 360° rotation of the stirrer