Deepening True Polarization Diversity for MIMO System

In our recent work, we have proposed several novel functions for accurately estimating the correlation and multiple-input-multiple-output (MIMO) capacity for combined spatial and true-polarization diversity (TPD) schemes. In this letter, we deepen TPD schemes, demonstrating that, with this technique, it is possible increase the capacity of the MIMO system. Moreover, we demonstrate that different TPD configurations (as a function of different spatial distributions, a different number of elements, and various distances between elements) have different TPD solutions in order to reach the maximum capacity. That is, it is necessary to choose a different TPD configuration to maximize MIMO capacity in each spatial configuration, especially when the area available for the antennas is very small; this is the case for most wireless devices where the antennas are one of the latest design constraints.