Integrated Spectrum Sensing and Frequency Reconfigurable Antennas for Inter-Weave Cognitive-Radio Applications

A dual-port antenna configuration composed of an ultra-wideband (UWB) sensing antenna and a dual-band reconfigurable communicating antenna is proposed and studied in this paper. The sensing antenna is an elliptical disk radiator covers a frequency range of (1.8-11) GHz. The communicating antenna is a modified dual-band rectangular radiator. By controlling the length of a stub attached to the communicating antenna with the aid of two PIN-diodes, the dual-band antenna can reconfigure its resonant frequencies to (2, 2.2) GHz, (3.25, 3.8) GHz, and (4.3, 5.6) GHz. Both simulated and experimental results for the return loss, mutual coupling, radiation patterns and gain are presented, and they reveal the antenna compatibility with the inter-weave cognitive radio applications. (paper)