Power amplifier breakthroughs may unlock applications in low-cost satellite communications
01 April 2013
Two DARPA sponsored research teams have achieved world record power output levels using silicon-based technologies for millimeter-wave power amplifiers.
RF power amplifiers are used in communications and sensor systems to boost power levels for reliable transmission of signals over the distance required by the given application. Further integration efforts may unlock applications in low-cost satellite communications and millimeter-wave sensing.
The first team, from the University of Southern California and Columbia University, achieved output power levels of nearly 0.5W at 45GHz with a 45 nanometer silicon CMOS chip. This world record result for CMOS-based power amplifiers doubles output power compared to the next best reported CMOS millimeter-wave power amplifier. The chip design used multiple stacked 45 nanometer silicon-on-insulator CMOS devices for increased effective output voltage swing and efficient eight-way on-chip power-combining.
The second team, made up of MIT and Carnegie Mellon University researchers, demonstrated a 0.13 micrometer silicon-germanium (SiGe) BiCMOS power amplifier employing multistage power amplifier cells and efficient 16-way on-chip power-combining.
This amplifier has achieved power output of 0.7W at 42GHz, a 3.5 times increase in output power compared to the next best reported silicon-based millimeter-wave power amplifier.
“Millimeter-wave power amplifiers have been demonstrated at this power level before, but this is a record with silicon-based technologies,” said Sanjay Raman, DARPA programme manager.
“Producing this level of output with silicon may allow integration on a chip with complex analogue and digital signal processing. In the 42-25GHz range, this would enable high bandwidth/data-rate transmitters needed for satellite communications at potentially very low cost and size, weight and power.”