Multiband MIMO antenna with a band stop filter for high isolation characteristics

In this paper, an internal multiband MIMO antenna with high isolation characteristic for LTE/WCDMA/HSDPA/M-WiMAX applications was proposed. A band stop filter is added at the corner of each radiating elements in order to enhance the isolation characteristic at LTE band. The fabricated antenna has the isolation of about 24 dB at the lower band and higher than 13 dB at the higher band. The measured peak gains of two antenna elements are -7.5 dBi and -6.4 dBi at the LTE band, 3.5 dBi and 2.9 dBi at the WCDMA/HSDPA band and 4.2 dBi and 3.5 dBi at the M-WiMAX band, respectively. The simulated and measured results show that the proposed multiband MIMO antenna could be a good candidate for 4G mobile systems.