A novel hybrid antenna capable of both spectrum sensing and frequency reconfigurability is proposed in this paper. The proposed hybrid antenna senses spectrum over a wide frequency range from 1 GHz-12 GHz and accordingly reconfigures its operating frequency in any of the four different frequencies i.e., 2.1 GHz, 2.96 GHz, 3.5 GHz and 5 GHz. Since wideband response for spectrum sensing and each frequency state works independently, there is no interference among various signals. The wideband response for spectrum sensing is obtained by exciting semicircular arc having staircase-shaped slot in the ground plane. Frequency reconfiguration is achieved by electronic switching among various matching stubs. Both simulated and experimental results for the return loss, gain and radiation patterns are presented. The proposed hybrid antenna shows a measured return loss better than -20 dB in all the operating bands, a bidirectional radiation pattern and 4.8 dB gain in θ = 20˚ and 120˚ in E plane.
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