Office of Technology Transfer – University of Michigan

Highly Efficient Miniaturized Slot Antenna

Technology #2271


Antennas have found numerous applications, especially as transmit and receive modules combined with miniaturized sensors and transducers in wireless systems. While recent advances in solid state devices and microelectromechanical systems (MEMS) technology have led to the realization of miniaturized, high performance antennas, efficiency and configurability of these antennas are less explored.


Researchers at the University of Michigan have developed designs and fabricated miniaturized, re-configurable resonant slot antennas, which takes advantage of its topology for miniaturization. The slot radiating elements have a planar geometry and can transmit vertical polarization when placed nearly horizontal. In addition, this resonant narrow slot antenna simplifies impedance matching, as slot dipoles can be excited by a microstrip line and be matched to arbitrary line impedances by moving the feed point along the slot. Using this design concept, antenna as small as 0.05 lambda0 by 0.05 lambda0 with a fairly high efficiency of -3 dBi was accomplished. Since there are no polarization or mismatch losses, the antenna efficiency is limited only by the dielectric and Ohmic losses of the substrate on which the antenna is made.


  • Wireless systems in devices such as radios, keyless entry systems, cell phones, and global positioning systems


  • Planar structure with low profile
  • Exhibits band selectivity and anti-jam characteristics -Can be easily integrated with other radiofrequency and microwave circuits


Miniaturized UHF Resonant Slot Planar Antenna