A Ka-Band Low-Loss SPDT Switch with Gate Floating Technique

In this paper, a low loss single-pole double-throw switch (SPDT) is presented for Ka-band (32–38 GHz) application. The switch is based on the shunt transistor with an impedance matching network. The gate floating method is used to enhance the power handling capability. Meanwhile, the transistor size is optimized by the tradeoff between the insertion loss and isolation. The measurement results of the proposed SPDT switch show that the insertion loss is less than 2.5 dB, and the isolation is greater than 19 dB across 32–38 GHz. The overall chip size is 0.5 mm
²
, including RF and DC pads.