Planar multiband MIMO antenna system operating in GSM 1800, LTE2300, LTE2500, WLAN and WIMAX bands

This paper presents a novel multiband planar diversity antenna covering five frequency bands for personal wireless communication system.The dual antenna system consists of two symmetric inverted L-shaped monopole antennas along with capacitively coupled Rectangular Open Ring Resonator (RORR) and spiral structure that generate resonant modes covering GSM 1800, LTE2300, LTE2500, WiMAX and WLAN frequency bands. Two protruded ground branches and Mshaped neutralization line are introduced to improve the bandwidth and isolation respectively. The isolation achieved is higher than 15 dB in the lower bands and 20 dB in the upper band, leading to an envelope correlation coefficient of less than 0.025. A prototype antenna is fabricated and tested for Sparameters and diversity performance which validates the use of proposed antenna for wideband applications.