A 270-to-300 GHz Amplifier-Last Transmitter With 6.7 dBm Peak Output Power Using 130 nm SiGe Process

This paper presents an amplifier-last transmitter (TX), operating from 270 -to- 300 GHz, in a 130 nm SiGe BiCMOS process. The TX is composed of a 250 GHz multiplier-by- 6 local oscillator (LO) chain, an-isolation-enhanced fundamental mixer, and a four-stage $g_{m}$-boosting power amplifier (PA). The measured peak output power of the LO chain is 7.8 dBm at 250 GHz. The TX achieves a measured peak $P_{\text {sat }}$ of 6.7 dBm at 278 GHz and $282 \mathbf{~ G H z}$, and delivers a measured maximum $O P_{1 d B}$ of $\mathbf{5} \mathbf{~ d B m}$ at 280 GHz with 3 dB bandwidth larger than 26 GHz. The meaured LO leakage and image siganal rejection are better than 21.7 dBc and 34.1 dBc respectively. For the first time, the silicon-based PA is integrated with 300 GHz TX, and the TX achieves the highest $P_{\text {sat }}$ and $O P_{1 d B}$ compared to other state-of-the-arts $\gt250 \mathrm{GHz}$ silicon-based TX.