The main problems associated with modern antenna designs comes down to size, efficiency and manufacturability. In wireless devices, the antenna takes up a disproportionate amount of space either leaving less room for other components and features or constraining the physical size of the device or both. Professors Anthony Grbic and Stephen Forrest at the University of Michigan have come up with a super-efficient, hemispheric antenna design that is small… as in tiny small.
In the past, antenna size and efficiency have been subject to the “Chu limit,” established in 1948 by L.J Chu, which postulates the maximum efficiency of an antenna design at any given size. Mass produced antennas for wireless devices, such as mobile phones, commonly are etched onto printed-circuit boards or made using 3D inkjet printing which serially builds the antenna geometry in 3D. However, neither comes close to reaching the Chu limit.
The prototype hemispheric antenna, however, is so efficient that it has three times the conductivity of 3D printed antennas and has 1.8 times the fundamental antenna size as described by the Chu limit – meaning that for the efficiency achieved, the projected antenna should be 1.8 times larger than it actually is. The genius of the design comes from the hemispheric shape which creates an antenna in 3D space that enhances signal reception regardless of the direction of the wireless signal.
The current design is tuned to 1.5GHz which is close to frequencies commonly used for consumer wireless communications such as for mobile phones and WiFi. But according to Grbic, as long as you can describe the data rate and frequency requirements, they can custom design an antenna while making it as small as possible. The upside to this is that the antenna designs can be mass produced in volume quickly and cheaply.
What this means is that future wireless gizmos and gadgets can get smaller or become more fully featured without sacrificing reception quality. The applications go well beyond mobile handset devices and may find uses in other device categories such as notebooks, tablets and even passive wireless sensor devices. Now this is tech we can all use.