Small Bandwidth SPDT Switch with Ideal Switch Uneven U-Shape Dumbbell DGS for 5G mm-Wave Application

The use of ideal switches Uneven U-shape Dumbbell DGS for the small bandwidth response of a mm-wave SPDT discrete switch in a 5G application is discussed in this study. Mathematical analysis of the DGS and the SPDT switch are discussed in this paper for the bandstop and allpass responses. The SPDT switch with ideal switches DGS in open circuit and short circuit conditions was constructed and simulated in CST Microwave Studio software to analyse its performance. During ideal switch in OFF state (open circuit), the DGS is active and proven to have bandstop properties at 26 GHz region with an attenuation response bandwidth of approximately 6.11 GHz at 10 dB and a maximum attenuation level (S21) of 31 dB. During an ideal switch in the ON state (short circuit), the DGS is inactive, resulting in a wideband allpass response with an insertion loss (S21) approximately 0.5 dB and an input reflection coefficient (S11) of more than 10 dB. As a result, the SPDT switch produces a useable small bandwidth isolation with an FBW of 11.62%. As a result, it meets the cognitive radio requirement for the 5G mm-wave front-end system.