This article presents the performance analysis of the multiple-input-multiple-output antenna systems,for mobile WiMAX handset applications. To investigate the effect of changing antenna arrangements on the antenna performance. we propose four kinds of two antenna structures considering the practical ground size of a mobile handset. To estimate the proposed structures, mutual coupling and envelope correlations were considered. Also the channel capacity and correlation were measured in the reverberation chamber. The relations between all parameters were analyzed based on the measured results. (C) 2009 Wiley Periodicals. Inc. Microwave Opt Technol Lett 51: 1558-1561, 2009 Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24344