A broadband coupled resonator decoupling network for a three-element compact array

Compact antenna arrays are getting more and more popular in a communication terminal to achieve higher packet rate and diversity gain. To reduce the strong mutual coupling and correlation due to the small spacing between the array elements, some kinds of decoupling means must be taken. In this paper, a coupled resonator decoupling network for a three element antenna array is proposed for the first time. Compared to the existing techniques, the network is more effective, simple and broadband. A prototype three-port decoupling network together with a compact three-monopole array is fabricated and measured. Measured results demonstrated that the radiation efficiencies are well maintained and envelope correlations are reduced significantly for all three elements.