Design of rectangular printed planar antenna via input impedance for supporting mobile wireless communications

We present a printed planar antenna suitable for mobile wireless communications. Since the printed antenna is easy to fabricate due to its simplicity, low cost, and light weight, it is widely used in communication systems. The conventional patch antennas take too much surface area to be applied to a mobile receiver. Although the size is reduced using the printed antenna, a reasonably wide bandwidth should still be considered. To overcome the disadvantage of narrow bandwidth, the substrate should be physically thick and the dielectric constant should be smaller. We suggest a simple form of printed planar antenna and show the optimal input impedance depending on the antenna size and operating frequency. The performance evaluation is achieved analytically for a prototype antenna model.