ABSTRACTIn recent works, it is demonstrated that, depending on the different spatial distributions and distance between elements, there exists a different true polarization diversity (TPD) configuration that provides a high improvement in terms of capacity. This means that it is necessary to choose the appropriate TPD configuration to maximize the multiple-input-multiple-output (MIMO) capacity. In this work, a genetic algorithm is used to optimize the element positions for four new different configurations in combination with the TPD technique. It is shown that, for some configurations, the same polarization option is always found to reach the maximum capacity. Based on this, some novel design rules are provided to maximize MIMO capacity when the area for placing the antennas is very small. This is the case for most of the wireless devices, where the antenna design and location is one of the latest design constraints to be taken into consideration in the device design.