Researchers at Northeastern University have made a major advance in developing significantly smaller antennas, hundreds of times tinier than currently existing versions. The development is significant because, in a world in which virtually every piece of portable wireless communications technology has shrunk over time, antennas have stubbornly remained the same size.
“Current antennas are limited to large sizes, which are hard for many applications like bio-implantable, bio-injectable, and bio-ingestible antennas,” Nian Sun, a professor of electrical and computer engineering at Northeastern, told Digital Trends.
The antennas described by Sun and his colleagues are based on an entirely different design principle to the traditional ones currently used. Traditional antennas receive and transmit large electromagnetic waves, and have to remain a certain size to function with electromagnetic radiation. Northeastern’s new antennas, on the other hand, are designed for acoustic resonance, which have a wavelength thousands of times smaller than electromagnetic waves.
The team has so far developed two types of acoustic antenna. The first has a circular membrane and is used for frequencies in the gigahertz range — including those frequencies used for Wi-Fi. The other acoustic antenna has a rectangular membrane for megahertz frequencies, typically used for TV and radio. Each antenna measures under a millimeter and both could be placed together on one chip. In tests, the new acoustic antennas have been shown to work better than traditional antennas in certain contexts.
Some of the potential applications for the new acoustic antennas include shrinking the size of technologies ranging from smartphones to satellites, which rely on antennas for communication. However, the really exciting possible uses involve incorporating antennas into technologies that are not yet in mass-market existence — opening up the possibility of ingestible antennas, brain implants, and the like.
As to what’s next for the project? “Further improving the acoustic antenna performance, and applying them to wireless communication systems,” Sun said. He acknowledges that the present models are still a proof-of-concept rather than a finished product but the researchers are optimistic about what is next. “We are in the process of commercializing these antennas now,” Sun said.
A paper describing the research was recently published in the journal Nature Communications.