A wideband monopole antenna for PCS/IMT-2000/Bluetooth applications

Abstract
A triple-band stubby antenna, fed by a coaxial probe, and a tuning technique are proposed for operating at PCS, IMT-2000, and Bluetooth bands. The proposed antenna, shielded by the antenna cover, consists of two radiating elements. The impedance matching and bandwidth for the proposed antenna are mainly affected by the length of the ground patch at the bottom of a small substrate. By properly choosing the size of the ground patch, the resonant frequencies can be easily adjusted, and a wide impedance bandwidth of 59.7% (|S/sub 11/| < -10 dB), which covers the Korean PCS (1750-1870 MHz), IMT-2000 (1920-2170 MHz), and Bluetooth (2402-2483.5 MHz) can be achieved. An omnidirectional radiation pattern is obtained, and a peak antenna gain of about 3 dBi or more is measured. The electrical characteristics of the proposed antenna make it attractive for use in mobile handset applications.