H-plane 3-dB hybrid ring of high isolation in substrate-integrated rectangular waveguide (SIRW)

An H-plane hybrid ring 3-dB power divider constructed with substrate integrated rectangular waveguide (SIRW) is proposed. Theoretical simulations are carried out at the X- and Ka-bands. The results show that the isolation between two output ports is high up to 35 dB and good 3-dB power division within the band of interest is observed also, that is, less than 0.3-dB derivation in the band of interest. In addition, the simulation results at the X-band shows a bandwidth of 10% at −15 dB. A prototype in the Ka-band is fabricated and the measured data at the Ka-band shows a bandwidth of 7% at −15 dB, in good agreement with simulation.