0.5W X-band SiGe PA with integrated double-tuned transformers

Power amplifier (PA) for a next generation X band T/R-modules in active array antennas is realized using low cost, high yield and high integration 0.18μm SiGe-HBT Technology. A single stage class AB cascode PA using only high-speed HBTs and double tuned transformers at the input and output matching networks with excellent performances has been designed. The PA achieve peak output power of 27dBm and maximum 36 % power added efficiency (PAE). The core RF size is 0.85mm × 0.56mm without pads and low frequency decoupling capacitors exhibiting an output power density of 1.0 W/mm
²
. To our knowledge, those values are the highest in SiGe-HBT power amplifiers.