Filtering Power Divider / Combiner Using Substrate Integrated Waveguide ( SIW ) - Based 180 o Hybrid

This paper presents a filtering power divider (PD)/power combiner (PC) using substrate integrated waveguide (SIW)-based 180 hybrid. The utilized 180 hybrid includes a standard H-plane 3-dB coupler and a broadband 90 phase shifter. The phase shifter is composed of non-radiating longitudinal slots patterned on the top conducting surface of the SIW. We have added the filtering property to the structure by an array of dissimilar transverse slots. The slots dimensions are obtained by the extracted external quality factor, coupling coefficient and the relationship between them and the slots dimensions. The proposed structure is designed for 8.2 GHz and investigated by ADS simulator. The results show the fractional bandwidth of the sum and difference ports are 13.7% and 14.93%, respectively. For sum operation, the minimum insertion loss is 3.78 dB and the return loss is above 25 dB in the passband. For difference operation, the minimum insertion loss is 3.81 dB and the return loss is above 26 dB in the passband.