(英) |
In recent years, Multiple-Input Multiple-Output (MIMO) is known as an elemental technology for next-generation communication, and reduction of mutual coupling between antenna elements (hereinafter referred to as decoupling) has become important. Various methods have been proposed for decoupling between two antenna elements, and the method using a bridge line is one of the simplest methods. However, when the antenna elements are connected by the bridge line, the resonant frequency changes, so it is necessary to readjust the size of the antenna to tune the resonant frequency to the desired frequency. Therefore, this method is not suitable when it is difficult to readjust the size of the original antenna due to design constraints. In this study, we propose a decoupling method that does not require readjustment of the size and structure of two planar inverted-F antennas (PIFA) by using a structure that combines parasitic elements and a bridge line. First, we consider decoupling corresponding to a single frequency. Next, in order to expand the applicable range of the proposed decoupling method, we propose another the decoupling method corresponding to dual-frequency. The simulations in this study are performed using the CST simulator and their validity is confirmed by measuring fabricated prototype of the antennas. |