A 128-GHz Broadband CMOS Amplifier with Distributed Resonance Frequencies of Parasitic Shunt LC Resonators

The realization of ultra-high-speed wireless communications in the 300-GHz band is expected. A 300-GHz transceiver requires broadband intermediate-frequency amplifiers in the D-band. To realize a broadband amplifier in the D-band, we propose an amplifier with distributed resonance frequencies of shunt LC resonators. The resonators are composed of the gate-to-drain parasitic capacitances and the shunt inductors in the gate-side intermediate networks. To achieve a flat frequency response, the number of high frequency resonators should be greater than the number of low frequency resonators. The proposed amplifier is fabricated using a 45-nm SOI CMOS process. It is shown that the proposed amplifier has the center frequency of 128 GHz, the gain of 10.4 dB and the -3 dB bandwidth of 19 GHz. The performance of the proposed amplifier is compared to the state-of-the-art CMOS amplifiers, and it is shown that the proposed amplifier achieves wide bandwidth in the D-band.