Modified Small PIFA Frequency Tunable Antenna

This paper presents a physically compact, frequency tunable antenna design for use in mobile terminals. The full operating bandwidth is between 1750 MHz and 2400 MHz with good impedance match in the entire tuning range to meet the coverage requirements of the DCS, PCS, UMTS and WLAN bands . The antenna bandwidth is is realized by loading the embedded resonant slot of a PIFA, with a varactor diode, with an equivalent capacitance range of 0.5 pF to 2.5 pF.