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The main purpose of this paper is to present a method for electrically reconfiguring the operating frequency of a planar monopole antenna. In this method a tuning circuit composed of a RF PIN diode switch and two discrete passive components is built inside the antenna structure. This allows a DC control voltage to be brought to the diode switch along with the RF signal. Thus, this method of tuning does not require separate DC wiring, unlike commonly used structures proposed by Zachou et al. The method presented is demonstrated with a dual-band monopole antenna applicable in a mobile handset. The antenna has the capability of switching the lower band between the GSM850 and GSM900 frequency ranges with only a minor impact on the upper band. The upper band covers the frequency ranges of the GSM1800 and DCS 1900 telecommunication standards. Along with the antenna structure, the measured return loss and far-field gain are presented and discussed.