A Parallel Ladder Structure for Mutual Coupling Reduction to Ultra-Wideband Antenna in E-Plane

A novel ultra-wideband decoupling structure for Vivaldi antenna array in E-plane is proposed and discussed in this paper. The decoupling structure is composed of 5 parallel staggered ladders with steps in bow-tie shape. The isolation between the two ports of the adjacent antenna is reduced more than 30 dB at 1.72 GHz and 3.58 GHz. And the proposed structure exhibits good decoupling performance between 0.5-2.4 GHz and 2.7-5.7 GHz. The pattern and realized gain are almost the same between the decoupled and the original antenna array.