APERTURE-COUPLED FREQUENCY-RECONFIGURABLE STACKED PATCH MICROSTRIP ANTENNA (FRSPMA) INTEGRATED WITH PIN DIODE SWITCH

Abstract

In this paper, a new Frequency-Reconflgurable Stacked Patch Microstrip Antenna (FRSPMA) with a new coupling method applied in an aperture-coupled technique controlled by the switching circuit is presented. This antenna uses a combination of aperture- coupled technique and stacked patch in order for the radiating elements to increase the bandwidth. Two shapes (I-shape and H-shape) and sizes of aperture slots are etched onto the ground with a purpose to couple the energy between feedline and stacked patch. One PIN diode switch is integrated in the feed network to control the length of the feedline. A variation of the feedline length controls the selected aperture slots to be active. The waves from the selected activated aperture slots will radiate to particular radiating patch (top or bottom patch) and achieve the frequency reconflgurability. When the switch is in ON mode, the antenna has a capability to conflgure its operating frequency at 2.6GHz and at 3.5GHz during the OFF mode. Besides that, the air gap is used to improve and avoid any coupling problem between the aperture slots and both of the two patches. Improper alignment between the aperture slots and patches will interfere waves radiating from aperture slots to the particular patch. In addition, the proposed antenna produces a high gain of more than 5dB during ON or OFF modes, respectively. The simulated results are compared with measured results.