An E-Band Gate-Pump SSB Mixer for Vital Signs Doppler Radar

In this paper, we propose a CMOS gate-pump single side band (SSB) mixer at E-band. To improve conversion gain and efficiency, the transistors M1-M4 are biased at near class B region with the LO signal. We also carefully select LO power to get optimum conversion gain. Compared with traditional gate-pump mixer, the LO of this mixer is applied to the gate and the IF is applied to the source. This approach can assure that transistors are biased in class B region and also improve linearity. The peak conversion gain is −11.98 at 72 GHz. The measured LO-to-RF isolation is better than 35 dB and IRR is better than 29 dBc from 68 - 80 GHz. To our best knowledge, this SSB mixer has the highest IRR and good conversion gain at E-band among passive SSB mixers.