38–80 GHz SPDT traveling wave switch MMIC utilizing fully distributed FET

This is the first report of the traveling wave SPDT switch using the fully distributed FET (FD-FET). The broadband characteristics were successfully obtained over more than an octave frequency range from Ka to W bands for the millimeter-wave applications. From 38 to 80 GHz, the low insertion loss of less than 2.1 dB, and the high isolation of better than 25.5 dB, were achieved by using the AlGaAs/InGaAs hetero-j unction FET traveling wave switch (TWSW) technology. In the design, the difference between the quasi- and the fully distributed switch circuit has been investigated.