An Ultra-Compact 64–98GHz Power-Combining Frequency Doubler with Magnetic-Enhanced Harmonic Reflectors

This article presents a compact 64–98GHz power-combining frequency doubler with magnetic enhanced harmonic reflectors. The 2ndharmonic outputs of two identical push-push frequency doublers are combined to improve the maximum output power. Two ways share an L-C harmonic reflector, and each way employs a C-L harmonic reflector. Two C-L harmonic reflectors are magnetically coupled to enhance each other and save area. Fabricated in a 65-nm bulk CMOS technology, the doubler achieves a 3dB bandwidth of 64–98GHz, a peak saturation output power of 11.4dBm, a maximum drain efficiency of 21.1%, a maximum conversion gain of 3.3dB, with a core area of only 0.053mm2.