Smaller Antennas Could Further Shrink Hand-held Electronics

  • Published
  • By Robert White
  • Office of Scientific Research
ARLINGTON, Virginia --  Just when it appeared that our hand-held electronic devices could not get smaller or more efficient, a research program funded by the Air Force Research Lab developed an innovative fabrication process to produce small, efficient antennas about the size of a quarter.

Dr. Anthony Grbic leads a team of researchers in the Department of Electrical Engineering and Computer Science at the University of Michigan; their research is supported by a Presidential Early Career Award for Scientists and Engineers through the Air Force Office of Scientific Research. Dr. Grbic and his colleague, Dr. Stephen Forrest, point out that in most cases the size of the antenna within a wireless device is what limits how small the device can be--manufacturers must "build up" to the required antenna size. Dr. Grbic's team provides a way for manufacturers to either "build down" to a much smaller size, or, with a smaller antenna, to allow additional room for more capabilities. The key to this new design is the hemispherical shape that takes advantage of volume--imagine the top half of a sphere with a descending spiral antenna winding down to the bas: instant miniaturization.

Dr. Grbic notes that this hemispherical antenna concept has been around for several years, but there was no practical way to mass produce the pattern. The Grbic and Forrest teams overcame this obstacle with a simple metallic stamping process that is very quick, efficient and potentially inexpensive, while maintaining the same bandwidth as their larger counterparts. Currently, this antenna design operates in only one frequency band, so the next step is to make the antenna operate in multiple frequency bands for use in multiple applications. Talks are under way with Bluetooth and WiFi communications manufacturers to utilize this new technology.

The Air Force is particularly interested in using these antennas on autonomous micro-air vehicles. Taking the process one step further, the technique could be applied to the manufacture of conformal antennas that could be then integrated onto the surface of an air vehicle--conforming to their low profile stealth design.