Isolation Enhancement in Closely Spaced Horn Antenna Using Decoupling Surface

The paper presents a decoupling surface (DS) designed to improve isolation between the elements of a conical horn antenna array. The operating frequency band of the horn antenna array spans the Ku-band (11.9 GHz - 18 GHz). Due to the close arrangement of the antenna elements, the isolation between them is relatively poor. By adding a periodic patch structure at the aperture of the horn antenna, the propagation of coupled waves is suppressed, significantly reducing the coupling between the antenna elements. Simulation results show that the proposed surface can enhance the port isolation between antenna elements by more than 20 dB, without affecting the antenna’s performance.