Estimating polarization information using vector antennas is of great significance in signal processing. However, the antenna patterns are normally assumed ideal without considering practical factors, such as cross polarization. Moreover, pattern calibration is required in data processing. In this work, we first illustrate the polarization estimation method, taking into account the cross polarization of antennas. To simplify the estimation, we introduce a practical co-located antenna pair comprising a sleeve monopole and a windmill loop, which share mostly identical radiation patterns but orthogonal polarizations. The cross polarizations of both antennas are below -20 dB. Besides, the phase and amplitude patterns of both antennas are almost omnidirectional in the azimuth plane, avoiding complicated calibrations. Attributed to orthogonal polarizations, good isolation is achieved, and the envelope correlation coefficient is below 0.01. With the proposed antenna, the axis ratio and phase difference of the incoming wave are reasonably estimated without pattern calibration and compensation. The co-located antenna pair was fabricated, using which the polarization information of a commercial WLAN antenna has been measured.
"Simplified Polarization Estimation Using Co-Located Antennas," Progress In Electromagnetics Research C,
Vol. 101, 43-52, 2020. doi:10.2528/PIERC19100102
1. Tian, Y., B. Wen, J. Tan, and Z. Li, "Study on pattern distortion and DOA estimation performance of crossed-loop/monopole antenna in HF radar," IEEE Trans. Antennas Propag., Vol. 64, No. 11, 6095-6106, Nov. 2017. doi:10.1109/TAP.2017.2755442
2. Slater, M. J., C. D. Schmitz, M. D. Anderson, D. L. Jones, and J. T. Bernhard, "Demonstration of an electrically small antenna array for UHF direction-of-arrival estimation," IEEE Trans. Antennas Propag., Vol. 61, No. 3, 1371-1377, Mar. 2013. doi:10.1109/TAP.2012.2227921
3. Pralon, M. G., G. D. Daldo, M. Landmann, M. A. Hein, and R. S. Thoma, "Suitability of compact antenna arrays for direction of arrival estimation," IEEE Trans. Antennas Propag., Vol. 65, No. 12, 7244-7256, Dec. 2017. doi:10.1109/TAP.2017.2757968
4. Li, H., S. Sun, and J. Wang, "Direction of arrival estimation using amplitude and phase information in low-profile MIMO arrays," IEEE Trans. Antennas Propag., Vol. 66, No. 11, 6457-6462, Aug. 2018. doi:10.1109/TAP.2018.2866989
5. Liu, Y. and L. Huang, "Pattern compensation for DOA estimation by electromagnetic vector sensors," Proc. International Conf. Microwaves, Radar and Wireless Communications (MIKON), Gdansk, Poland, 2014.
6. Balanis, C. A., Antenna Theory — Analysis and Design, 3rd Ed., John Wiley & Sons, 2005.
7. Kim, D. S., C. H. Ahn, Y. T. Im, S. J. Lee, K. C. Lee, and W. S. Park, "A Windmill-shaped loop antenna for polarization diversity," Proc. IEEE Antennas Propag. Soc. Int. Symp., 361-364, Honolulu, Jun. 2007.
8. Wong, K. T., L. Li, and M. D. Zoltowski, "Root-MUSIC-based direction-finding and polarization estimation using diversely polarized possibly collocated antennas," IEEE Antennas Wireless Propag. Lett., Vol. 3, 129-132, 2004. doi:10.1109/LAWP.2004.831083
9. Yuan, X., K. T. Wong, and K. Agrawal, "Polarization estimation with a dipole-dipole, a dipole-loop, or a loop-loop pair of various orientations," IEEE Trans. Antennas Propag., Vol. 60, No. 5, 2442-2452, May 2012. doi:10.1109/TAP.2012.2189740
10. Xuan, X., "Spatially spread dipole/loop quads/quints: For direction finding and polarization estimation," IEEE Antennas Wireless Propag. Lett., Vol. 12, 1081-1084, 2013.
11. Shen, L., Z. Liu, and Y. Xu, "Parameter estimation using partly calibrated vector antennas," IEEE Antennas Wireless Propag. Lett., Vol. 16, 860-863, 2017. doi:10.1109/LAWP.2016.2611612
12. Best, S. R., "The electrically small dipole-loop pair revisited," Proc. IEEE Antennas Propag. Society Int. Symp., 2265-2268, 2007.
13. Kim, J. and Y. Rahmat-Samii, "Integrated low-profile dual loop-dipole antennas using an embedded electromagnetic bandgap structure," Microw. Opt. Technol. Lett., Vol. 49, No. 5, 1085-1089, May 2007. doi:10.1002/mop.22342
14. Wong, K. T., Y. Song, C. J. Fulton, S. Khan, and W. Y. Yam, "Electrically ‘long’ dipoles in a collocated orthogonal triad — For direction finding and polarization estimation," IEEE Trans. Antennas Propag., Vol. 65, No. 11, 6057-6067, Nov. 2017. doi:10.1109/TAP.2017.2748183
15. Khan, S., K. T. Wong, Y. Song, and W. Y. Tam, "Electrically large cirlular loops in the estimation of an incident Emitter’s direction of arrival or polarization," IEEE Trans. Antennas Propag., Vol. 66, No. 6, 3046-3055, Jun. 2018. doi:10.1109/TAP.2018.2819727
16. Ebihara, S., A. Uemura, T. Kuroda, and H. Soda, "Dipole array antenna and loop antenna for estimation of direction and polarization in borehole radar," Proc. 15th International Conference on Ground Penetrating Radar, 780-784, Brussels, Belgium, Jun. 2014.
17. Duplouy, J., C. Morlaas, H. Aubert, P. Potier, P. Pouliguen, and C. Djoma, "Reconfigurable grounded vector antenna for 3D electromagnetic direction finding applications," IEEE Antennas Wireless Propag. Lett., Vol. 17, No. 2, 197-200, 2018. doi:10.1109/LAWP.2017.2779878
18. Xiong, J., M. Zhao, H. Li, Z. Ying, and B. Wang, "Collocated electric and magnetic dipoles with extremely low correlation as reference antenna for polarization diversity MIMO applications," IEEE Antennas Wireless Propag. Lett., Vol. 11, 423-426, 2012. doi:10.1109/LAWP.2012.2195150
19. 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. doi:10.1049/el:20030495