Summary
International Symposium on Antennas and Propagation
2011
Session Number:ThE3
Session:
Number:ThE3-5
Simple Design of Decoupling Network Considering Mutual Admittance in Array Antenna
Naoya Yamaki, Naoki Honma,
pp.-
Publication Date:2011/10/25
Online ISSN:2188-5079
Summary:
In the next-generation mobile communication systems, high performance antennas are required for the base station, i.e., they must have high radiation efficiency and the radiation pattern suitable for the system requirement. In the base station, the transmitted signal from the base station leaks into the receiving antenna by mutual coupling. Therefore, it is difficult to process the received signal from the mobile terminal. Due to the influence of the mutual coupling, it is difficult to offer technical advantages of the antenna. A DMN (Decoupling and Matching Network) is an effective measure in reducing such mutual coupling [1], [2]. However, the circuit complexity is a serious problem in achieving a feasible DMN for the array antenna with three or more antenna elements when the conventional method is used [1]. Another research has shown that the DMN design using bridge susceptance using lumped element can offer a simple circuit configuration when the number of the antenna elements is two [2]. However, it is difficult for applying this method to the array with many more antennas. It is also problem that the radiation pattern of the antenna is changed and the bandwidth is decreased by employing conventional method. As described above, much simpler decoupling network is needed to offer a feasible DMN. In this paper, a simple design of decoupling network considering a mutual admittance is proposed. For configuring decoupling network, microstrip line(MSL) is used. By using MSL, a low-less reactive element can be easily configured. In our technique, the mutual admittance can be cancelled by connecting MSL between two neighbouring antenna ports as bridge susceptance. In the following part of the paper, the idea and design method of the decoupling network are described. From measurement of S-parameter, the effectiveness of the proposed method is denoted