A Wide-Band 90 degree HMSIW Schiffman Phase-Shifter for 28 GHz Millimeter-Wave Applications

In this paper, a 90 degree phase-shifter built by half mode substrate integrated waveguide (HMSIW) for mm-Wave applications is presented. The design is based on conventional Schiffman phase-shifter and employs a coupled HMSIW and a uniform HMSIW to create differential phase-shift. A magnetic wall transition technique is used to mirror the HMSIW's magnetic wall enabling a low loss U-turn. The HMSIW provides low loss, high power handling capability (inherited from SIW), and compact design. The implemented prototype provides relatively constant 90 degree phase-shift for frequency band starting from 21 GHz to 32 GHz equivalent to 40.74% of the center frequency (27 GHz). The insertion loss during the bandwidth is around 2.5 dB and the input reflection is below −10 dB.