On Closely Coupled Dipoles with Load Matching in a Random Field

MIMO is a wireless communication technology that is growing in popularity due to its ability to deliver significant improvements over conventional systems. However, some applications require antennas to be closely spaced, which results in strong coupling among the antennas and performance degradation. Here we show that in a random field, load impedance can play an important role in the power, correlation and capacity performance of MIMO systems. While a good choice of load impedance can alleviate the loss of power and correlation performance, capacity performance is less sensitive to load variation. Moreover, the phase component of open circuit correlation has been found to have a significant influence on MIMO performance, indicating that important information is lost if it is neglected. A comparison between the performance metrics over different load impedances indicates that capacity depends largely on received power and not correlation

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