Densely packed MIMO antenna array integrated with compact resonator for high isolation

This paper presents a densely packed MIMO antenna array with high isolation. A compact resonator as a band-gap filter is designed between the two patch antennas to enhance the isolation. Thanks to this compact resonator, the isolation between two patches can reach 30dB, nearly 20dB higher than the MIMO antenna array without using decoupling network. Furthermore, he bandwidth and radiation pattern of the proposed antenna array are nearly the same with the traditional one. Moreover, the envelope correlation coefficient of proposed antennas is smaller than −40 dB. Compared with the previous works, the elements spacing of the proposed antenna array is much smaller, about 0.04λ
0
.