## 4 Results and Discussion of SPDT SW2  
Figure 11a shows the measured and simulated IL (i.e., \(S_{12}\)I) and isolation (i.e., \(S_{32}\)I) of SPDT SW2 in the TX mode. SPDT SW2 achieves a measured \(\Pi_{\mathrm{min}}\) of 0.74 dB at 20.2 GHz and an IL better than 1.2 dB for 13.6-30.5 GHz, corresponding to a bandwidth of 16.9 GHz. Figure 10: (**a**) Measured \(P_{out}\) and IM3 versus \(P_{in}\) characteristics of SPDT SW1 in the TX mode at 28 GHz. (**b**) Measured \(P_{1\mathrm{dB}}\) and IIP3 versus frequency characteristics of SPDT SW1 in the TX and RX modes. Figure 9: Measured and simulated \(P_{1\mathrm{dB}}\) in (**a**) the TX mode, and (**b**) the RX mode of SPDT SW1 at 28 GHz. This result is close to the simulated one, i.e., an IL\({}_{\text{min}}\) of 0.7 dB at 21.5 GHz and an IL lower than 1.2 dB for 12.4-38.1 GHz, corresponding to a bandwidth of 25.7 GHz. The decent IL is attributed to the low-loss of the equivalent \(\lambda\)/4-TL, the good TX-to-RX isolation, and the high impedance of the off-state DTMOS-R M\({}_{1}\). Moreover, SPDT SW2 achieves a measured \(\text{IS}_{32}\text{l}_{\text{max}}\) of 59.2 dB at 30 GHz and isolation of 25.2-59.2 dB for 13.6-30.5 GHz. This result is close to the simulated one, i.e., an \(\text{IS}_{32}\text{l}_{\text{max}}\) of 62.4 dB at 26.9 GHz and isolation of 29.7-62.4 dB for 13.6-30.5 GHz. Figure 11b shows the measured and simulated \(\text{S}_{11}\) and \(\text{S}_{22}\) of SPDT SW2 in the TX mode. SPDT SW2 achieves a measured \(\text{S}_{11,\text{min}}\) of \(-\)15.9 dB at 20.2 GHz and an \(\text{S}_{11}\) better than \(-\)10 dB for 12.6-37.3 GHz, equivalent to an \(\text{f}_{\text{10 dB}}\) of 24.7 GHz. This result is close to the simulated one, i.e., an \(\text{S}_{11,\text{min}}\) of \(-\)26.4 dB at 24.7 GHz and an \(\text{f}_{\text{10 dB}}\) larger than 38.4 GHz (11.6-50 GHz). Moreover, SPDT SW2 achieves a measured \(\text{S}_{22,\text{min}}\) of \(-\)30.7 dB at 20.7 GHz and an \(\text{S}_{22}\) better than \(-\)10 dB from 10.9 GHz to larger than 50 GHz, equivalent to an \(\text{f}_{\text{10 dB}}\) larger than 39.1 GHz. This result is close to the simulated one, i.e., an \(\text{S}_{22,\text{min}}\) of \(-\)28.2 dB at 46.4 GHz and an \(\text{f}_{\text{10 dB}}\) larger than 39 GHz (11-50 GHz). Figure 11c shows the measured and simulated IL (i.e., \(\text{IS}_{31}\)) and isolation (i.e., \(\text{IS}_{21}\)) of SPDT SW2 in the RX mode. SPDT SW2 achieves a measured \(\text{IL}_{\text{min}}\) of 1.93 dB at 40.2 GHz and an IL of 1.93-2.5 dB from 27.7 GHz to over 50 GHz. This result is close to the simulated one, i.e., an IL\({}_{\text{min}}\) of 1.99 dB at 34.2 GHz and an IL of 1.99-2.5 dB for 25.9-43.9 GHz. Moreover, SPDT SW2 achieves a measured isolation of 17.5-21.8 dB for 27.7-50 GHz. This result is close to the simulated one, i.e., isolation of 19.5-26.2 dB for 27.7-50 GHz. Figure 11d shows the measured and simulated S\({}_{11}\) and S\({}_{33}\) of SPDT SW2 in the RX mode. SPDT SW2 achieves a measured \(\text{S}_{11,\text{min}}\) of \(-\)13 dB at 41.4 GHz and an \(\text{S}_{11}\) better than \(-\)10 dB from 27 GHz to over 50 GHz, corresponding to an \(\text{f}_{\text{10 dB}}\) larger than 23 GHz. This result is consistent with the simulated one, i.e., an \(\text{S}_{11,\text{min}}\) of \(-\)12.9 dB at 35.3 GHz and an \(\text{f}_{\text{10 dB}}\) of 16.9 GHz (27.6-44.5 GHz). Moreover, SPDT SW2 achieves a measured \(\text{S}_{33,\text{min}}\) of \(-\)49.2 dB at 31.4 GHz, and an \(\text{S}_{33}\) better than \(-\)10 dB for 11-48.5 GHz, equivalent to an \(\text{f}_{\text{10 dB}}\) of  
Figure 11: Measured and simulated (a) IL and isolation and (b) \(\text{S}_{11}\) and \(\text{S}_{22}\) of SPDT SW2 in the TX mode. Measured and simulated (c) IL and isolation and (d) \(\text{S}_{11}\) and \(\text{S}_{33}\) of SPDT SW2 in the RX mode. 37.5 GHz. This result is consistent with the simulated one, i.e., an \(\rm S_{33,min}\) of \(-\)44.1 dB at 28.5 GHz and an \(\rm f_{10 dB}\) of 23.3 GHz (17.1-40.4 GHz).