Stirrer swing experiment in reverberation chambers

It is often to see that stirrers mainly rotate about their axes, generate cylindrical volumes as big as possible, which is of importance for the efficiency of the stirrers. However it has been proved that it is mainly the periphery of the stirrers (including inner radius and outer radius) that contributes in the tuning of reverberation chambers. In this paper, we have investigated the design parameters for efficient stirring in reverberation chambers. And a swing stirrer consisting of two blades have been attained which rotates only 180 degree or even smaller instead in a circle. Then we measured the efficiency of the swing stirrer in terms of the lowest possible frequency for which it gives a certain number of uncorrelated samples. The result shows that the swing stirrer's efficiency is quite good compared with normal Z stirrer. And moreover the parameters of field uniformity between swing stirrer and normal Z stirrer also have a good linear relation, which shows that the law of both is also similar. In a word, by increasing the main factor of the stirrer (swing radius), the swing stirrer's stirrer efficiency has been improved observably.