A novel dual-port dual-layer planar spiral slot multiband antenna.

In order to realize a dual-port multiband antenna, a novel planar spiral slot antenna is proposed and analyzed. The antenna adopts a dual-layer substrate structure. A spiral slot is etched on its bottom metal surface with a ring gap beside the slot to improve the isolation and lower the frequency. An elliptical metal ring radiation unit in the middle surface of the antenna plays the role of radiating and impedance matching. Two mutually perpendicular microstrips on the upper surface are used for feeding the radiation unit. The simulation and test results show that two ports of the antenna can work at multiple frequencies with the same radiator, and the isolation is more than 13.5 dB in the working bands (1.86-1.99 GHz, 2.47-2.5 GHz, 2.57-2.64 GHz, 2.90-5.7 GHz and 6.35-9.66 GHz). The antenna has the advantages of high gain, small volume, quasi omnidirectional radiation, and so on. [ABSTRACT FROM AUTHOR]