Compact High-Gain Antennas for High-Efficiency Wireless Communications

Technology #15952

Questions about this technology? Ask a Technology Manager

Download Printable PDF

Yong Kyu Yoon
Seahee Hwangbo
Hae Yong Yang
Managed By
Richard Croley
Assistant Director 352-392-8929

To Reduce Size, Any Type of Antenna Can Be Integrated on This Fractal Rectangular Reactive Impedance Surface

This Fractal Rectangular-Reactive Impedance Surface can be utilized to reduce an antenna’s size and achieve compact high-gain antennas for high-efficiency wireless communication systems. Planar antennas have become highly desirable for wireless communication systems in recent years due to the ease of fabrication and integration as well as compactness and low-profile characteristics. The desirable electrical and physical characteristics can be achieved through the substrate design. Use of a reactive impedance surface as a substrate for planar antennas enhances the bandwidth and radiation characteristics of an antenna. Researchers at the University of Florida have developed a Fractal Rectangular-Reactive Impedance Surface that can reduce the antenna size while still creating compact high-gain antennas. Any type of antenna can be integrated on top of the FR-RIS while still maintaining efficiency and size reduction.


Fractal Rectangular-Reactive Impedance Surface (FR-RIS) for antenna miniaturization for high-efficiency wireless communication systems


  • Compensates for capacitive impedance of the antenna, reducing antenna size
  • Controls the resonant frequency and the surface impedance of the reactive impedance surface through fractal-rectangular structure, achieving high-gain and antenna efficiency


Using this Fractal Rectangular-Reactive Impedance Surface (FR-RIS) structure reduces antenna size, increases inductive impedance, and achieves compact high-gain antennas for high-efficiency wireless communication systems. In contrast to the Conventional Rectangular-Reactive Impedance Surface (CR-RIS), this Fractal Rectangular-Reactive Impedance Surface (FR-RIS) does not have rectangular metal patches between the two substrates. Instead the unit cell of the FR-RIS shows a scalable fractal-rectangular shape. A gap between the metal patches produces inductance, capacitance, and determines the resonant frequency. Increasing or decreasing the length or width of the gap between the unit cell of the FR-RIS changes the fractal patterns without changing the total size of the unit cell, which allows for antenna miniaturization. University of Florida researchers have reduced an antenna by 20 percent using FR-RIS .