Patch antennas using embedded lumped element delay line for size reduction

Small antennas have a wide range of applications in modern personal communications. This paper presents a systematic design methodology to reduce the antenna size by using lumped elements in the antenna structure. These lumped elements change the current distribution on the patch and can lower the resonant frequency. Some simple lumped element delay lines are introduced and the resonant frequency variation is studied for different cases. Measured results demonstrate good agreement with numerical analysis. It is also shown that cross polarization can be controlled with the introduction of the embedded lumped elements.