An exciting research collaboration between UCL and Chalmers University of Technology in Sweden has resulted in the design and testing of the widest band amplifier ever reported, operating at at 235 GHz, twice as fast as the previous best. This has potential applications in imaging and the future generation of communications systems.
The work was led by Professor Herbert Zirath, Head of the Microwave Electronics Laboratory at the Department of Microtechnology and Nanoscience at Chalmers UT and Professor Izzat Darwazeh, Head of the Communications and Information Systems Group in UCL Electronic and Electrical Engineering. Zirath and Darwazeh started on the joint project aiming to design circuits suited for communication at frequencies approaching the terahertz (THz) region. As communication demands increase and more and more bits must be sent every second, amplifiers with greater bandwidth are required, driving this research.
A set of amplifier circuits were designed by PhD student Klas Eriksson, manufactured by Teledyne Technologies in the USA and characterised at Chalmers. The research team was delighted that the new amplifiers tested achieved results so close to design predictions. They demonstrated exceptionally wide broadband operation, from low GHz frequencies to frequencies exceeding 235 GHz. The gain provided exceeded 15dB, translating to a gain bandwidth product of approximately 1.5 THz. The design team believes this amplifier is at least twice as fast (in terms of bandwidth) as the fastest amplifier reported to date. The circuit is reckoned to be capable of handling 250,000,000,000 bits per second.
Professor Darwazeh said:
“This achievement was made possible by excellent technological advances in nanotechnology, and state of the art design processes and techniques. This technology will help make ultrafast broadband possible for widespread use not only in communication systems, but also in instrumentation for scientific and test and measurement purposes.”
The circuit builds on previous research and design work reported by Zirath and Darwazeh over the past two decades, including a previous circuit that was the fastest in the world.
Professor Zirath said:
“This result is of considerable interest for the development of new products within the area of communication and instrumentation such as fast oscilloscopes, pulse amplifiers and fast fiber optic receivers.”
Details of the work will be reported at the forthcoming IEEE International Microwave Symposium (IEEE-IMS) to be held in Florida in June 2014.