SIW SPDT switch based on switchable HMSIW units

A novel SIW SPDT switch based on switchable HMSIW unit was proposed in this work. The concept of switchable HMSIW units with shorted and opened stubs were studied, investigated and compared, bandwidth enhancement method for switchable units was proposed and demonstrated. Based on these switchable units, HMSIW/SIW-based SPDT switch were designed, fabricated and measured. Measured results show that return loss was better than 15 dB over the frequency from 4.65 GHz to 5.43 GHz, in which the insertion loss was less than 1.78 dB and isolation was higher than 28.5 dB.