Gielen, SenneSenneGielenGungor, BerkeBerkeGungorZhang, YangYangZhangIngels, MarkMarkIngelsReynaert, PatrickPatrickReynaert2026-03-162026-03-162025979-8-3315-1412-91529-2517https://imec-publications.be/handle/20.500.12860/58843This paper presents a compact D-band Doherty power amplifier (PA) in 250-nm InP DHBT. The power amplifier core consists of a stacked common-emitter and common-base pair and utilizes an integrated 1:4 Guanella transformer for interstage matching. A power detector as well as an adaptive bias network are also implemented to boost the linearity and efficiency of the amplifier. The PA achieves a small-signal gain of 17.8 dB and a small-signal bandwidth of 14.7 GHz. In continuous-wave measurements, the power amplifier has a saturated output power of 20.3 dBm. The amplifier achieves a maximum power-added efficiency (PAE) of 21.4% and 11.5% with 6-dB power backoff. The performance of the amplifier is verified with modulated measurements up to 24 Gb/s.engProceedings paper10.1109/rfic61188.2025.11082824WOS:001546480000058