A Millimeter-Wave Ultra-Wideband Polyphase Frequency Doubler With 88% FBW and Inherent Harmonic Cancellation in 22nm FDSOI

This paper presents a 22-57 GHz frequency doubler that uses two push-push class-C active stages and a differential I-Q input signal to generate a differential output signal at twice the input frequency. A two-stage transformer-based input quadrature coupler generates the required quadrature signals. The symmetric, multi-stage design of the coupler improves the phase and amplitude imbalance, and enables inherent higher-harmonic cancellation over a wide bandwidth. Implemented in GF22nm FDSOI, the doubler has an area of 1000 $\mu$ m 700 $\mu$ m excluding pads. The circuit draws < 17 mA from a 0.8 V supply at 9 dBm input power, and achieves a peak output power of 2.9 dBm, 15.8% drain efficiency and an instantaneous 3-dB fractional bandwidth (FBW) of 88%.