Winning Watts

Macquarie University electronics PhD student Michael Boers has defeated competitors from universities in the USA, Canada and Korea by designing and building an ultra-efficient radio frequency (RF) power amplifier.

Boers won the annual the Institute of Electrical and Electronic Engineers Microwave Techniques and Technology Society's (MTT-S) High Efficiency Power Amplifier Design Competition, held in Hawaii at the beginning of June, which was timed to coincide with the International Microwave Symposium (IMS) and the Radio Frequency Integrated Circuit (RFIC) conference.

Designing better microwave power amplifiers is the focus of much international academic and commercial attention due to our need to more efficiently convert electrical power to the microwave energy required by today's wireless systems such as satellite transceivers, cellular base stations and most importantly cell phones where high efficiency translates directly to battery life (that is, the higher the efficiency, the longer one can talk on a given cell phone).

The IEEE's MTT-S therefore sponsors an annual competition, open to university students around the globe, to design a power amplifier with the greatest efficiency. Competitors are required to design, construct and measure a high efficiency power amplifier, at a frequency of their choice above 1 GHz but less than 20 GHz, and having an output power level of at least 5 watts, but less than 100 watts. The winner is judged on the design which demonstrates the highest power added efficiency.

Boers' winning amplifier can operate between 1 and 2GHz (i.e. at cell phone frequencies), but is most efficient at around 1.2GHz where its efficiency has been measured at about 80 per cent and where it draws 290mA from a 29Volt supply. It is capable of outputting up to 10 watts. Boers' engineering win is akin to a gold medal at a world championship in the sporting world.

The competition focus was squarely within Boers' area of expertise - his research at Macquarie, which he is completing at the Centre for Microwave and Wireless Applications under the supervision of Profs Neil Weste and Tony Parker, is focused on millimetre-wave IC design for future ultra broadband 60 GHz wireless systems.

‘In particular I am interested in system-level design, transmitter architectures, high efficiency power amplifier design as well as methods which will reduce the time-to-market and cost of millimetre-wave IC systems,’ he said.

This work was made possible with the support of NHEW R&D and Applied Wave Research.

Michael Boers can be reached at mboers@ics.mq.edu.au