Antenna with a reduced ground plane size

Small size antennas are an important consideration for today's wireless personal communication systems. Microstrip antennas are good candidates for these systems. Ground plane size reduction is becoming more important given the limited area available on the intended device. Truncating the ground plane has adverse effects on the antenna. This paper shows these effects and presents the design of a new antenna type that uses nonplanar rings. Simulated and experimental results demonstrate that excellent size reduction is obtained while at the same time achieving good gain and radiation characteristics.