Expanding the Lowest Usable Frequency of Reverberation Chambers Through Stirrer Design

This paper investigates improving a reverberation chamber's lowest usable frequency (LUF) through stirrer design changes to enhance measurement accuracy in the low-frequency range.The modelling of a reverberation chamber with different stirrers was performed using Altair FEKO software, where near-field data was requested in the working volume.A MATLAB processing script was used to calculate factors such as resonant frequencies, number of modes, and standard deviation, to determine the LUF of each design setup.The results indicated that increased surface area in stirrer design improves the LUF between 4 and 47 MHz, depending on the design changes.A similar experiment calibrating SARAO's three reverberation chambers with different stirrer designs and comparing their theoretical LUF against their measured LUF verified the modeled results but will be reported elsewhere.