Dual Polarized Triple Band Hybrid MIMO Cylindrical Dielectric Resonator Antenna for LTE2500/WLAN/WiMAX Applications

In this communication, triple band hybrid multi-input-multi-output (MIMO) cylindrical dielectric resonator antenna (CDRA) with high isolation is examined. The proposed MIMO antenna includes two symmetric folded microstrip line feeding structures along with CDRA at two different ends of substrate. Two inverted L-shaped strips on the ground plane are used to enhance the isolation (S-12<-15 dB) as well as to generates 2.7 GHz frequency band. Metallic strip on the ground plane act as an electromagnetic reflector and also enhance the isolation between two antennas (S-12<-20 dB). Archetype of proposed MIMO antenna design has been fabricated and tested to validate the simulated results. The proposed antenna operates at three different frequency bands 2.24-2.38 GHz, 2.5-3.26 GHz, and 4.88-7.0 GHz (S-11<-6 dB) with the fractional bandwidth 6.06%, 26.4%, and 35.7%, respectively. Folded microstrip lines generate lambda/4 path delay between the electric field lines and originate circular polarization characteristics in the frequency range 5.55-5.75 GHz with the fractional bandwidth of 3.55%. In order to satisfy the different performance requirement of MIMO antenna such as envelop correlation coefficient, mean effective gain, effective diversity gain, peak gain are also examined. The proposed antenna is found suitable for LTE2500, WLAN, and WiMAX applications. (C) 2016 Wiley Periodicals, Inc.