A decoupling technique for increasing the port isolation between two closely packed antennas

A general decoupling technique for increasing the port isolation between two closely packed antennas is proposed in this paper. The two antennas are first modeled by a π-shaped circuit from its S-parameters. Then, the detailed decoupling method is discussed to increase the port isolation where an optimization objective of maximum energy unbalance is adopted. Taking two closely parked patch antennas for example, good agreements between the theoretical analysis and full wave simulation are obtained. The present technique can increase the port isolation, thus the total efficiency, correlation coefficient and diversity gain are improved. Such a general decoupling technique can also be applied to any other antenna types.