A Compact Microstrip Power Divider Using Periodic DGS and HIOS

In this paper, miniaturized branch-line couplers (BLCs) are designed, simulated and fabricated using FR4 substrate at the operating frequency 2.4GHz. First, high impedance open stubs (HIOS) are used to miniaturize the conventional BLC using the combinational-model (combinational of T and …-model). The proposed design is reduced by more than 57.5% compared to the conventional design. The second step is to use defected ground structure (DGS) underneath the BLC. The proposed design is capable to achieve any dividing ratio without reducing the width of the line, which means that the power handling capability is not reduced. In addition, suppression of higher order modes is achieved and more than 18% reduction in size as compared to the conventional shape is obtained. As a flnal step, the two techniques are combined together and a third BLC is proposed. Good agreement is found between experimental and simulated results using the software package Zeland IE3D.