Carousel stirrer efficiency evaluation by a volumetric lattice-based correlation matrix

Recently, a new stirrer shape, the carousel stirrer, has been proposed to improve the reverberation chamber performances. In this contribution, we propose a method to compute the number of uncorrelated positions of the carousel stirrer. This method works by counting the low-correlation elements of a 3D lattice-based correlation matrix, each elements of the matrix being the Pearson correlation between two random vectors sampled at two different stirrer locations. We use ad-hoc FDTD code to simulate the Cartesian fields within the reverberation (lattice) region, for a large number of stirrer positions. Our analysis highlights dependence on the considered volume dimensions, the number of lattice field samples, and their spatial distance. The study also reveals the presence of periodic frequencies where uncorrelation dramatically reduces. A parametric analysis is presented to investigate the reason of this phenomenon which is evident only for two Cartesian field components.