A High-Efficiency E-Band SiGe HBT Frequency Tripler with Broadband Performance

A compact E-band frequency tripler with broadband performance is implemented in a 0.13 µm SiGe BiCMOS technology. A high pass filter and transformers impedance matching were used in a fully differential cascode topology to improve the harmonic suppression and broadband performance. Besides, a RF virtual ground capacitor in parallel with base of the CB transistor was proposed in the buffer stage that can enhance the output power by more than 1.7 dB. Followed by a buffer amplifier, the proposed tripler exhibits a measured 3-dB bandwidth ranging from 69 to 86 GHz with a peak output power of 9.9 dBm at 78 GHz. The suppression of fundamental and second-harmonic frequency is more than 35 and 33 dBc, respectively. The tripler can work properly between industrial temperature range (-40°C to 125°C). The tripler with buffer amplifier occupies only 158 mW from a 3.3 V supply. To the best of our knowledge, the proposed tripler demonstrates the highest output power and DC-to-RF efficiency, largest harmonic suppression that covers industrial temperature range compared with other silicon based E-band triplers.