SIW/HMSIW-to-microstrip transitions using lumped-elements and their quadrature power divider application

In this work, a SIW-to-microstrip (MS) and a HMSIW-to-MS transition structure using lumped-elements for their quadrature power divider application are proposed. The proposed lumped element structure offers functions of transitions between the SIW/HMSIW and the MS, and ±45° phase shift as well as has a size effective merit in the SIW/HMSIW integrated circuits. The measured quadrature power divider showed an equal power division and a good phase balance between output ports across 4.49 - 5.40 GHz frequency range. The proposed structure may contribute for designing a balanced amplifier in compact SIW circuit and system.