While the size of portable devices continue to shrink, the wavelength of the TV signals being used to broadcast mobile DTV remain the same. While most of the focus on miniature antennas has been for wireless and broadband use, they potentially could be used to improve TV reception on hand held devices. One design that's been used for miniaturizing an antenna is to make it into a hemispherical shape – a spiral wrapped around half of a sphere. The problem is these structures are hard to manufacture. Dr. Anthony Grbic and his team of researchers at the Department of Electrical Engineering and Computer Science at the University of Michigan have come up with way to mass produce these antennas using a simple metallic stamping process which is quick, efficient and potentially inexpensive. The antennas created using this process should maintain the same bandwidth as larger conventional antennas.
The current design operates on only one frequency band. The next step is to add multiband capability. Testing is currently underway with Bluetooth and WiFi communications manufacturers.
The research is supported by a Presidential Early Career Award for Scientists and Engineers through the Air Force Office of Scientific Research. The Air Force is interested in using this technology for conformal antennas on aircraft.
This information was from an Air Force Office of Scientific Research news release on Eurekalert. In search for additional information, I found a pay-walled article Printing tiny coiled antennas on Nature.com. I found an interesting University of Michigan paper covering a wider range of research on small antennas in Miniaturized Antennas for Platform-level Integration Scenarios by Wonbin Hong.