In this paper, a novel wideband quasi-Yagi antenna is proposed and investigated for multiple-input multiple-output (MIMO)/diversity antennas applications. An aperture-coupled balun is adopted with a curved Yagi radiator for the antenna to realize wideband property. The proposed quasi-Yagi antenna has high radiation efficiency and stable end-fire radiation patterns, operating in a wide bandwidth from 7 to 13.8 GHz. Then a pattern diversity antenna is developed using two elements, which are overlapped partly and placed in opposite orientations. The measured 10-dB bandwidth of the MIMO antenna is from 6.3 to 13.6 GHz. Meanwhile, isolation between the two ports is better than -26 dB. The radiation patterns and envelope correlation coefficients are also presented. The proposed pattern diversity antenna is validated to perform stable behaviours over a wide bandwidth, and it will find applications in wireless communications and radars systems.
2. Kan, H., et al., "Simple broadband planar CPW-fed quasi-Yagi antenna," IEEE Antennas Wireless Propag. Lett., Vol. 6, 18-20, 2007.
3. Deal, W. R., N. Kaneda, J. Sor, Y. Qian, and T. Itoh, "A new quasi-Yagi antenna for planar active antenna arrays," IEEE Trans. Microw. Theory Tech., Vol. 48, No. 6, 910-918, Jun. 2000.
4. Ma, T.-G., C.-W.Wang, R.-C. Hua, and J.-W. Tsai, "A modified quasi-Yagi antenna with a new compact microstrip-to-coplanar strip transition using artificial transmission lines," IEEE Trans. Antennas Propag., Vol. 57, No. 8, 2469-2474, Aug. 2009.
5. Nikolic, N. and A. Weily, "Compact E-band planar quasi-Yagi antenna with folded dipole driver," IET microwaves, Antennas Aropag., Vol. 4, No. 11, 1728-1734, 2010.
6. Wang, Z., et al., "A novel design of folded dipole for broadband printed Yagi-Uda antenna," Progress In Electromagnetics Research C, Vol. 46, 23-30, 2014.
7. Nguyen, P. T., A. Abbosh, and S. Crozier, "Wideband quasi-Yagi antenna with tapered driver," Proc. Asia-Pacific Conf. Antennas Propag., 138-139, Singapore, Aug. 2012.
8. Jiang, K., Q. G. Guo, and K. M. Huang, "Design of a wideband quasi-Yagi microstrip antenna with bowtie active elements," Proc. Int. Conf. on Microwave and Millimeter Wave Technology (ICMMT), 1122-1124, 2010.
9. Abbosh, A., "Ultra-wideband quasi-Yagi antenna using dual-resonant driver and integrated balun of stepped impedance coupled structure," IEEE Trans. Antennas Propag., Vol. 61, No. 7, 3885-3888, Jul. 2013.
10. Mattheijssen, P., M. H. A. J. Herben, G. Dolmans, and L. Leyten, "Antenna-pattern diversity versus space diversity for use at handhelds," IEEE Trans. Vehicular Technol., Vol. 53, No. 4, 1035-1042, Jul. 2004.
11. Waldschmidt, C. and W. Wiesbeck, "Compact wide-band multimode antennas for MIMO and diversity," IEEE Trans. Antennas Propag., Vol. 52, No. 8, 1963-1969, Aug. 2004.
12. Zhang, S., Z. Ying, J. Xiong, and S. He, "Ultrawideband MIMO/diversity antennas with a tree-like structure to enhance wideband isolation," IEEE Antennas Wireless Propag. Lett., Vol. 8, 1279-1282, 2009.
13. Luxey, C. and J.-M. Laheurte, "Dual-beam array of microstrip leaky-wave antennas," Inst. Elect. Eng. Electron. Lett., Vol. 34, 1041-1042, May 1998.
14. Hu, C. C., C. F. Jou, and J. J. Wu, "An aperture-coupled linear microstrip leaky-wave antenna with two-dimensional dual-beam scanning capability," IEEE Trans. Antennas Propag., Vol. 48, No. 6, 909-913, Jun. 2000.
15. Wu, P. and Q. Xue, "A wideband microstrip balun structure," 2014 IEEE Microwave Symposium (IMS), 1-3, Florida, Jun. 2014.
16. Blanch, S., J. Romeu, and I. Corbella, "Exact representation of antenna system diversity performance from input parameter description," Electron. Lett., Vol. 39, No. 9, 705-707, May 2003.