Abstract: An 8-16 GHz wideband power amplifier was implemented based on the 0.18 μm SiGe BiCMOS process. By using the peak-gain distribution technique, the bandwidth of the amplifier is expanded effectively without significantly deteriorating the available gain. The high output power is achieved by combining the output power of two PA cells using a transformer. The measured results show that the amplifier features a peak gain of 27 dB, and a 3-dB bandwidth of 6 GHz with a bandwidth ratio 54.5%. At the 3-dB bandwidth frequency ranges, the amplifier achieves a saturation output power from 17.5~20.5 dBm, while the power added efficiency is 12-18%. The whole chip including all testing pads is 1.0 mm².