A 110-to-130GHz SiGe BiCMOS Doherty Power Amplifier With Slotline-Based Power-Combining Technique Achieving >22dBm Saturated Output Power and >10% Power Back-off Efficiency

The demand for 100+Gbps data-rates in wireless communications has driven the rapid development of silicon-based transceivers in the mm-wave and sub-THz bands. The broad available spectrum in D-band (110 to 170GHz) is attracting interest for short-range and backhaul high-speed communication [1,2]. To overcome the high path loss, a high-power transmitter (TX) or power amplifier (PA) is essential in such systems. However, silicon-based mm-wave PAs encounter several challenges, such as the limited f
T
/f
max
of transistors, low breakdown voltage in CMOS/SiGe transistors, and the considerable loss of passive networks. Additionally, the widely employed high peak-to-average-power-ratio (PAPR) signal poses severe requirements for TXs/PAs, including peak efficiency and power back-off (PBO) efficiency. A solution to these challenges is proposed in this work and resulted in a D-band PA with >22dBm saturated output power (P
SAT
) and >10% PBO efficiency.