Differences in User Influence on MIMO Handset Antenna Performance in Reverberation Chamber

User influence on multiple-input multiple-output (MIMO) performance is studied for different dual antenna handsets specially designed to have good and bad MIMO performance. The study reveals that user influence can cause either improvement or degradation for different test objects, including a spread effect over the parameters. Differences in performance between good and bad handsets can be clear when they are measured without user influence, but become small under real person influence. This result illustrates the particular importance of user influence to characterize MIMO handsets.