A novel direction of arrival (DOA) and polarization estimation method with sparse conical conformal array consisting of concentred loop and dipole (CLD) pairs along the z-axis direction is proposed in this paper. In the algorithm, the DOA and polarization information of incident signals are decoupled through transformation to array steering vectors. According to the array manifold vector relationship between electric dipoles and magnetic loops, the signal polarization parameters are given. The phase differences between reference element and elements on upper circular ring are acquired from the steering vectors of upper circular ring, it can be used to give rough but unambiguous estimates of DOA. The phase differences are also used as coarse references to disambiguate the cyclic phase ambiguities in phase differences between two array elements on lower circular ring. Without spectral peak searching and parameter matching, this method has the advantage of small amount of calculation. Finally, simulation results verify the effectiveness of the algorithm.
2. Nehorai, A. and E. Paldi, "Vector-sensor array processing for electromagnetic source localization," 25th Asilomar Conf. Signals, Syst., Comput., 566-572, Pacific Grove, CA, 1991.
3. Wang, L. M., Z. H. Chen, and G. B. Wang, "Direction finding and positioning algorithm with COLD-ULA based on quaternion theory," Journal of Communications, Vol. 9, No. 10, 778-784, Oct. 2014.
4. Li, J., "Direction and polarization estimation using arrays with small loops and short dipoles," IEEE Trans. Antennas Propag., Vol. 41, No. 3, 379-387, 1993.
5. Wong, K. T. and M. D. Zoltowski, "Polarization diversity and extended aperture spatial diversity to mitigate fading-channel effects with a sparse array of electric dipoles or magnetic loops," IEEE Int. Veh. Technol. Conf., 1163-1167, 1997.
6. Wong, K. T. and M. D. Zoltowski, "High accuracy 2D angle estimation with extended aperture vector sensor arrays," Proc. IEEE. Int. Conf. Acoust., Speech, Signal Process., Vol. 5, 2789-2792, Atlanta, GA, May 1996.
7. Wong, K. T. and M. D. Zoltowski, "Uni-vector-sensor ESPRIT for multisource azimuth, elevation, and polarization estimation," IEEE Trans. Antennas Propag., Vol. 45, No. 10, 1467-1474, Oct. 1997.
8. Wang, L. M., L Yang, G. B. Wang, Z. H. Chen, and M. G. Zou, "Uni-Vector-sensor dimensionality reduction MUSIC algorithm for DOA and polarization estimation," Math. Probl. Eng., Vol. 2014, Article ID 682472, 9 Pages, 2014.
9. Li, J., R. T. Compton, and Jr., "Two-dimensional angle and polarization estimation using the ESPRIT algorithm," IEEE Trans. Antennas Propag., Vol. 40, No. 5, 550-555, May 1992.
10. Wang, L. M., M. G. Zou, G. B.Wang, and Z. H. Chen, "Direction finding and information detection algorithm with an L-shaped CCD array," IETE Technical Review, Vol. 32, No. 2, 114-122, 2015.
11. Li, J., R. T. Compton, and Jr., "Angle estimation using a polarization sensitive array," IEEE Trans. Antennas Propag., Vol. 39, No. 10, 1539-1543, Oct. 1991.
12. Yuan, X., K. T.Wong, and K. Agrawal, "Polarization estimation with a dipole-dipole pair, a dipoleloop pair, or a loop-loop pair of various orientations," IEEE Trans. Antennas Propag., Vol. 60, No. 5, 2442-2452, May 2012.
13. Wong, K. T. and A. K. Y. Lai, "Inexpensive upgrade of base-station dumb-antennas by two magnetic loops for “blind’ adaptive downlink beamforming," IEEE Antennas Propag. Mag., Vol. 47, No. 1, 189-193, Feb. 2005.
14. Wong, K. T., "Direction finding/polarization estimation — Dipole and/or loop triad(s)," IEEE Trans. Aerosp. Electron. Syst., Vol. 37, No. 2, 679-684, Apr. 2001.
15. Yuan, X., "Quad compositions of collocated dipoles and loops: For direction finding and polarization estimation," Antennas and Wireless Propagation Letters, Vol. 11, 1044-1047, Aug. 2012.
16. Li, Y. and J. Q. Zhang, "An enumerative nonLinear programming approach to direction finding with a general spatially spread electromagnetic vector sensor array," Signal Processing, Vol. 2013, No. 93, 856-865, 2013.
17. Gong, X. F., K. Wang, Q. H. Lin, Z. W. Liu, and Y. G. Xu, "Simultaneous source localization and polarization estimation via non-orthogonal joint diagonalization with vector-sensors," Sensors, Vol. 2012, No. 12, 3394-3417, 2012.
18. Josefsson, L. and P. Persson, "Conformal array antenna theory and design," Series on Electromagnetic Wave Theory, Wiley, IEEE Press, New York, 2006.
19. Balanis, C. A., Antenna Theory: Analysis and Design, Wiley, New York, 2005.
20. Hansen, R. C., P. T. Bargeliotes, J. Boersma, Z. W. Chang, K. E. Golden, A. Hessel, W. H. Kummer, R.Mather, H. E. Mueller, and D. C. Pridmore-Brown, Conformal Antenna Array Design Handbook, Department of the Navy, Air Systems Command, PN, 1981.
21. Wong, K. T. and M. D. Zoltowski, "Direction finding with sparse rectangular dual-size spatial invariance array," IEEE Trans. Aerosp. Electron. Syst., Vol. 34, No. 4, 1320-1327, Oct. 1998.
22. Zoltowski, M. D. and K. T. Wong, "Closed-form eigenstructure-based direction finding using arbitrary but identical subarrays on a sparse uniform cartesian array grid," IEEE Trans. Signal Process., Vol. 48, No. 8, 2205-2210, Aug. 2000.
23. Mathews, C. P. and M. D. Zoltowski, "Eigenstructure techniques for 2-D angle estimation with uniform circular array," IEEE Trans. Signal Process., Vol. 42, No. 9, 2395-2407, Sep. 1994.
24. Akkar, S., F. Harabi, and A. Gharsallah, "Concentric circular array for directions of arrival estimation of coherent sources with MUSIC algorithm," XIth International Workshop on Symbolic and Numerical Methods, Modeling and Applications to Circuit Design, 1-5, Gammath, Italy, Oct. 2010.
25. Wang, L. M., G. B. Wang, and Z. H. Chen, "Joint DOA-polarization estimation based on uniform concentric circular array," Journal of Electromagnetic Waves and Applications, Vol. 27, No. 13, 1702-1714, 2013.
26. Yuan, X., K. T. Wong, Z. X. Xu, and K. Agrawal, "Various compositions to form a triad of collocated dipoles/loops, for direction finding and polarization estimation," IEEE sensors Journal,, Vol. 12, No. 6, 1763-1771, 2012.