A compact dual-band inverted-F filtering antenna with good band-edge selectivity for modern wireless communication systems is presented in this paper. A novel dual-band filter based on open-loop dual-mode resonator loading a T-shaped stub and an inverted-F antenna (IFA) also with a T-shaped open stub are integrated together. The higher band is controllable easily by adjusting the dimension of the T-shaped stub, leaving the lower band unaffected. To minimize the dimension of the filtering antenna, the last stage of the filter is folded. A flat gain response is obtained with steep skirts at both band edges. Simulated and measured results show that the integration makes the proposed antenna operate at 2.4/3.7 GHz with compact size, good band-edge selectivity, and controllable higher band compared with the traditional IFA.
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