Use of Metamaterial Screens for Reducing Mutual Coupling Between Antennas Placed in Limited Space

A number of theoretical and experimental researches of influence of metamaterial electromagnetic screens on decoupling of closely placed antennas have been made. Complex antenna systems, closely placed on upper platforms of towers or masts, have been examined. Among peculiarities of these systems are high density of antenna systems, as well as severe restrictions on weight and dimensional parameters of antennas and places of their location, and also on location of various metal structures. In order to reduce mutual coupling between closely placed antennas it was suggested to use metamaterial screens. It was shown that this kind of screens has special characteristics as compared to conventional metal screens, namely, at an antenna’s natural frequency the screen is almost transparent for electromagnetic radiation, while at an operating frequency of interfering antenna it becomes ill-transparent and acts as a reflector. It was shown that the metamaterial screens are effective in case of compact arrangement of antennas, because, while having small dimensions of the structure, they can provide for reduction of mutual coupling between antennas without compromising the directional characteristics.