Wideband collocated antennas for multiple input multiple output (MIMO) systems are proposed. The structure is disposed on two substrate layers. On the first top substrate, a disc monopole is etched. The top of the second substrate contains a tapered slot antenna in a form of a Vivaldi antenna and two reflector elements in the form of half disc. The designed antenna can switch among five radiation patterns which radiate in different directions of space with only two excitation ports. All antennas have a relative bandwidth at least 23%. The antenna elements exhibit a low mutual coupling since they are around -17 dB over the considered bandwidths. This performance is believed because the disc monopole mainly has a broadside radiation while the Vivaldi antenna radiates in end-fire directions. With an overall length of about a half guided wavelength, the proposed structure is believed suitable for applications needing radiation pattern diversity.
2. Konanur, A. S., et al., "Increasing wireless channel capacity through MIMO systems employing co-located antennas," IEEE Transaction on Microwave Theory and Techniques, Vol. 53, No. 61, 1837-1843, 2005.
doi:10.1109/TMTT.2005.848105
3. Yahya, R., A. Nakamura, M. Itami, and T. A. Denidni, "A novel UWB FSS-based polarization diversity antenna," IEEE Antennas and Wireless Propagation Letters, Vol. 16, 2525-2528, 2017.
doi:10.1109/LAWP.2017.2730161
4. Mouffok, L., "A dual-band diversity antenna for LTE devices and human body effect," Microwave and Optical Technology Letters, Vol. 56, No. 12, 2795-2799, December 2014.
doi:10.1002/mop.28712
5. Boutayeb, H. and P.Waston, "Broadband collocated antennas with three orthogonal polarizations," European Conference on Antennas and Propagation (EUCAP), 2228-2232, 2017.
6. Yetisir, E., C. C. Chen, and J. L. Volakis, "Wideband lox profile multiport antenna with omnidirectional pattern and high isolation," IEEE Transactions on Antennas and Propagation, Vol. 64, No. 9, 3777-3786, 2016.
doi:10.1109/TAP.2016.2583468
7. Ramachandran, A., S. V. Pushpakaran, M. Pezholil, and V. Kesavath, "A four-port MIMO antenna using concentric square ring patches loaded with CSRR for high isolation," IEEE Antennas and Wireless Propagation Letters, Vol. 15, 1196-1199, 2016.
doi:10.1109/LAWP.2015.2499322
8. Mouffok, L. and F. Ghanem, "Wideband collocated antennas for radiation pattern diversity applications," IEEE International Symposium on Antennas and Propagation, 537-538, 2016.
9. Zhang, T., S. Y. Yao, and Y. Wang, "Design of radiation-pattern-reconfigurable antenna with four beams," IEEE Antennas and Wireless Propagation Letters, Vol. 14, 183-186, 2015.
doi:10.1109/LAWP.2014.2360098
10. Zhai, G., Z. N. Chen, and X. Qing, "Enhanced isolation of a closely spaced four-element MIMO antenna system using metamaterial mushroom," IEEE Transactions on Antennas and Propagation, Vol. 63, No. 8, 3362-3370, 2015.
doi:10.1109/TAP.2015.2434403
11. Nguyen, V. A., M. H. Jeong, M. T. Dao, and S. O. Park, "Four-port beam reconfigurable antenna array for pattern diversity system," IET Microwaves Antennas & Propagation, Vol. 6, No. 10, 1179-1186, 2012.
doi:10.1049/iet-map.2011.0606
12. Liao, W. J., C. Y. Hsieh, B. Y. Dai, and B. R. Hsiao, "Inverted-F/slot integrated dual-band four-antenna system for WLAN access points," IEEE Antennas and Wireless Propagation Letters, Vol. 14, 847-850, 2015.
doi:10.1109/LAWP.2014.2381362
13. Jusoh, M., T. Sabapathy, M. F. Jamlos, and R. Kamarudin, "Reconfigurable four-parasitic-elements patch antenna for high-gain beam switching application," IEEE Antennas and Wireless Propagation Letters, Vol. 13, 79-82, 2014.
doi:10.1109/LAWP.2013.2296491
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