A novel ultra wideband (UWB) multiple-input-multiple-output (MIMO) antenna with different polarizations and band-notch characteristics is proposed in this letter. The antenna consists of two monopole antenna radiating elements with gradual change structure, which are placed perpendicularly to each other and printed on each side of the substrate to achieve a wide bandwidth and different polarizations. Band-rejected filtering property in the WLAN band is achieved by etching a H-shaped slot and employing a resonant L-shaped strip on two antenna elements. The proposed antenna has a small size of 27×37×1 mm3 with a bandwidth of 128.6% (2.35-10.82 GHz). Within the required band, the isolation for the two ports exceeds 18 dB. The envelope correlation coefficient is also measured.
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