MIMO Performance and Uncertainty Analysis in a Reverberation Chamber With Phase Stirring

Source-stirred reverberation chamber (SSRC) is a typical type of reverberation chambers (RCs) that can produce an electromagnetic environment suitable for electromagnetic compatibility (EMC) testing without a mechanical stirrer. This article proposes an SSRC based on phased array antennas, which achieves stirring by changing the phase difference, helping to improve test efficiency and reduce costs. The stirring effects and the multiple-input multiple-output (MIMO) performance of SSRC is investigated, with a focus on the measurement and uncertainty analysis of the Rician K-factor. The results demonstrate that the phase stirring method can achieve sufficient stirring. Moreover, four sample selection methods are employed to evaluate the measurement uncertainty. It is found that the correlation matrix method yielding the smallest relative uncertainty among them, approximately 1.2$\%$ at 10 GHz. Through a uniformity and MIMO performance test, this article demonstrates the potential of phase stirring technology in EMC and MIMO over-the-air testing, providing a significant option for improving efficiency and reducing costs.