Ultra-Low Power K-band Frequency Doubler with Differential Output

This paper presents an ultra-low power K-band frequency doubler operating under 0.4 V supply voltage. With 0 dBm input signal, the frequency doubler consumes 2.4 mW and achieves -8.4 dB conversion gain. The measured saturated output power is -6 dBm at 23.6 GHz, and the 3-dB bandwidth is from 20.4 to 25.4 GHz. It exhibits up to 39 dB fundamental rejection. The proposed differential frequency doubler operates at an ultra-low supply voltage with ultra-low power consumption in active frequency doublers.