Maximum Doppler Frequency in Reverberation Chamber with Continuously Moving Stirrer

Reverberation chambers equipped with a continuously moving mechanical mode stirrer cause Doppler spread in the measured signal. In order not to affect the signal, the instrument used for recording the measurement samples should have an IF bandwidth that exceeds the maximum Doppler frequency of the reverberation chamber. The actual stirrer speed cannot be used to calculate the maximum Doppler frequency the usual way, because the resonances in the chamber enhance the effect of stirrer motion. A relation for the maximum Doppler frequency in reverberation chambers is derived, and measurements are performed to verify it.