Research on Cross-Band Decoupling of Dipole Antennas Using Loading Inductors

Cross-band coupling in shared-aperture base station will cause unwanted radiation performances. The decoupling effects of the inductance for dipole antennas with different frequencies are investigated in this paper. One pair of inductors are firstly symmetrically loaded into the two arms of the low-band dipole to change the field distributions and therefore improve the isolation in the high frequency band by 8.4 dB. Analysis of the decoupling function of the two pairs of inductors are further done. Simulation results show that the port isolation in the high frequency band is higher than 33.2 dB after two pairs of inductors are introduced. The proposed decoupling method shows attractive features in shared-aperture MIMO base station antenna array developments.