Design of a Ka/V-Band CMOS T/R Filter-Switch

Fully integrated 0.18-μm CMOS dual-band band-pass filtering transmit/receive (T/R) switch operating in two frequency bands of 35.5-43.7 GHz and 56.5-63 GHz is reported. The developed T/R switch consists of three SPDT switches, each designed based on a band-pass filter with shunt nMOS transistors performing the switching function. The measured insertion losses of the switch are 8.9/12.5 dB and 10/12.7 dB for the receiving and transmitting operations at 40/60 GHz, respectively. The measured stop-band rejection ratio between 40 GHz and 51 GHz is over 30/22 dB for the two operations, respectively. The measured isolation is 56/51 dB and 57/51 dB for the two operations at 40/60 GHz, respectively. The measured input 1-dB compression points of the switch are 23, 16.5 for single-tone 40-, 60-GHz input signal and 18/14 dBm at 40/60 GHz for concurrent dual-tone 40/60-GHz input signals for the transmitting operation, respectively. The total chip size is 1840 μm × 860 μm excluding all the on-wafer testing pads.