Wideband Half-Mode SIW Power Divider With Improved Output Isolation Using Slotline Isolation Technology

A wideband half-mode substrate integrated waveguide (HMSIW) power divider with bandpassfiltering response using the slotline isolation technology is presented in this paper. Resistive slot on the bottom layer is employed to improve the output isolation. To obtain filtering response, L-type slot line and two multimode SIR resonators loaded symmetrically at two sides of the input transmission line are employed to generate transmission zeros at upper stop band. In addition, filtering response is achieved by combining the inherent high-pass characteristic of the HMSIW and the TZs. The equivalent circuits are presented and analyzed by using evenand odd-mode method, and the relative design equations are derived. The measured return loss of the HMSIW power divider is about 10 dB and its isolation is greater than 15 dB from 3.8 to 5.8 GHz. All measured results show reasonable agreement with the simulated ones.