Wideband micromachined broadside coupled Schiffman phase shifter

A 15–45 GHz broadside coupled rectangular coaxial line based phase shifter is demonstrated. An analysis, the design, fabrication, measurements and a sensitivity study are conducted and discussed. Amplitude and phase imbalances of <0.25 dB and <2.5°, respectively, are measured. Input port reflection coefficients < −10 dB and an insertion loss below 0.6 dB are also obtained. A conducted sensitivity study shows the small dependence of the device performance on the process variations. The presented results may pave the way for multi‐octave analogue phase shifters and beamformers throughout the millimetre‐wave range.