Multi octave wideband CMOS circulator using 0.11 um process

A multi octave wide band, low noise 3-port CMOS circulator is proposed and implemented using 110 nm CMOS process. The circulator operates the frequency range from 0.25 GHz to 4 GHz with supply voltage of 3 V and -3 V. The measured insertion loss is 2 dB, return loss is better than 14 dB and isolation is more than 12 dB, respectively. The measured noise figure is from 7 to 10 dB over full frequency range.