Design Analysis of Wideband 24-40GHz GaN-on-Si SPDT Switches for 5G Millimeter-Wave Applications

Microwave switch design analysis using a 100 nm GaN-on-Si high-electron-mobility transistors (HEMTs) technology is discussed in this letter. Analyzed semi-quantitatively, the switch turn-on and turn-off channels are treated as Butterworth-type filters to better realize insertion loss (IL) and isolation optimization with the given bandwidth. An extra open-circuit transmission line is adopted in the input port to ensure better input impedance matching. As experimental vehicles for the presented analysis, two wideband high-power single-pole double-throw switches employing three-and four-shunt HEMTs were implemented separately for fifth generation millimeter-wave applications. Measurement results for these two cases demonstrate state-of-the-art IL of less than 1.4/1.65 dB and isolations of better than 28/34 dB for the wideband frequency range of 24-40 GHz.