Decoupling of Broadband Base Station Antennas Based on Microwave Absorber

In this paper, aiming at the coupling problem in base station antennas, a broadband microwave absorber working at 3.3-5 GHz is designed. The proposed microwave absorber compactly places two kinds of ring circuits loaded with patch resistors together. This compact placement method allows two ring loops to resonate simultaneously, expanding the bandwidth of the microwave absorber. The absorption rate of this broadband microwave absorber reaches more than 95 % in its working frequency band. To reduce the coupling between the base station antennas, the microwave absorber is applied to the base station antenna in this paper. The microwave absorber can achieve a 10 dB decoupling effect without affecting the overall performance of the antenna and this simulation results verify the feasibility of applying microwave absorber to base station antenna decoupling.