A reconfigurable dual-band MIMO antenna system for mobile terminals

In this paper, a varactor diode based two element reconfigurable, dual-band, multiple input multiple output (MIMO) antenna is presented. The single antenna element is a modified printed inverted F-shape antenna (PIFA) with radiating lines and a folded patch. This proposed structure is grounded by a metallic wall for size optimization and compactness. The proposed design is very versatile as it can be used to cover wide frequency bands for dual-band operation. The well known frequency bands covered are GSM-750, GSM-870, LTE-900, LTE-1800, with several other bands as well. The proposed design provides at least -12 dB isolation between its antenna elements. The dimensions of the proposed single element design were 12×30 mm² with a ground plane area of 65×120 mm².