Correlation coefficient control for a frequency reconfigurable dual-band compact MIMO antenna destined for LTE

In this contribution, we are proposing a compact design for an implementation of a two element MIMO antenna destined for LTE smart phones. The antennas are collocated at one end of the PCB to minimize antenna volume. Each element is dual-band and frequency reconfigurable using tunable capacitors. The MIMO performance is investigated in two different channel models through efficiency, branch power imbalance and envelope correlation. The proposed antennas have acceptable levels of isolation between them, even in the low-bands, while having a good efficiency. Furthermore, the correlation coefficient is controlled by manipulating the ground currents between the antennas using a tunable capacitor. Nonetheless, using this mechanism to control the coupling between the antennas, the total efficiency is affected.