A 124–152 GHz > 15-dBm $\mathbf{P}_{\text{sat}}$ 28-nm CMOS PA Using Chebyshev Artificial- Transmission-Line-Based Matching for Wideband Power Splitting and Combining

This paper presents a 124–152 GHz power amplifier (PA) with >15 dBm saturation output power $(\mathbf{P}_{\text{sat}})$ in a 28-nm CMOS process. Low-coupling transformer-based fourth-order matching networks are used to extend the bandwidth (BW) with low insertion loss and compact area. A four-way Chebyshev-type artificial-transmission-line-based power combiner is proposed to further improve the output power without sacrificing BW. The measurement results show that this P A can achieve a peak gain of 22.6 $\mathbf{dB}$ with 28 GHz 3-dB BW. The in-band $\mathbf{P}_{\mathbf{sat}}$ is >15 dBm with a maximum output power of 16.2 dBm at 135 GHz. The total area of the chip is $\mathbf{0.66}\mathbf{\times}\mathbf{0.73}\ \mathbf{mm}^{\mathbf{2}}$ •