A low-power K-band frequency synthesizer using push-push transformer-feedback VCO in 0.18-µm CMOS technology

In this paper, a K-band frequency synthesizer using 0.18-μm CMOS technology is presented. To achieve low-power consumption, a transformer-feedback voltage-controlled oscillator (TF-VCO) with a cascoded current mode logic (CML) frequency divider is proposed. Furthermore, the push-push structure is selected in TF-VCO to overcome the design trade-off between operating frequency and dc power consumption of CML divider. Based on the aforementioned techniques, the measured phase noise of proposed frequency synthesizer is -114 dBc/Hz at 10 MHz offset at 21.5 GHz. The total power consumption is 20.1 mW.