Jul 6, 2011 07:40 GMT  ·  By
A hemisphere-shaped antenna developed at the University of Michigan has the capacity to be mass produced and could lead to improvements in wireless consumer electronics
   A hemisphere-shaped antenna developed at the University of Michigan has the capacity to be mass produced and could lead to improvements in wireless consumer electronics

University of Michigan (U-M) experts have developed a method of producing extremely small antennas in mass. The thing about these minute devices is that they were miniaturized to a point where they are approaching the fundamental minimum size limit for their bandwidth.

What this means is that it will soon become impossible to miniaturize the devices even further. The U-M team believes that this innovation will lead to the emergence of the next generation of wireless consumer electronics and mobile devices, that could use the new antennas.

At this point, there are two ways in which the new technologies could conceivably be used. One way to develop it would be to make the devices smaller, while the second one would be to keep current sizes, but endow them with even more functions.

In standard mobile devices, the largest wireless component is typically the antenna. If the transmitter is made several times smaller, than designers could either make the device smaller, or introduce even more gadgets or components in the compartment that becomes available.

The new research effort was led by U-M Department of Electrical Engineering and Computer Science associate professor Anthony Grbic. He worked closely with colleague Stephen Forrest, who is a professor in the departments of Materials Science and Engineering and Physics at the university.

Together, the two spearheaded the development of new hemisphere-shaped antennas, which they say can be mass-produced via novel imprint processing techniques. The innovative methods are both inexpensive and fast.

Measurements of the antennas reveal that they are just 1.8 times larger than the minimum fundamental size that was calculated back in 1948 by expert L.J. Chu. This size is not fixed, but rather a function of the bandwidth at which the antenna operates.

“Ever since the Chu limit was established, people have been trying to reach it. Standard printed circuit board antennas don't come close. Some researchers have approached the limit with manually-built antennas, but those are complicated and there's no efficient way to manufacture them,” Grbic explains.

“We've found a way to reduce the antenna's size while maximizing its bandwidth, using a process that's amenable to mass production,” the investigator goes on to say. The U-M antennas operate at a frequency of 1.5 gigahertz, which is where most of the current WiFi devices also communicate.

The new investigation was made possible by funds provided by the Department of Education (DE) Graduate Assistance in Areas of National Need program, the US National Science Foundation (NSF) and the US Air Force (USAF) Office of Scientific Research.

The paper detailing the research – entitled “Novel Methods to Analyze and Fabricate Electrically Small Antennas” – will be presented at the 2011 IEEE International Symposium on Antennas and Propagation.