volume | PIER Journals

Abstract

A comprehensive study is performed to investigate the performance of a non-uniform circular array interferometer in a real time 3-dimensional direction finder. The angular range of view is supposed to be 65 degrees vertically and 120 degrees horizontally, which is suitable for airborne applications. Interferometer is designed to work in the S, C and X bands. Regarding optimization process, the interferometer employs an eight element non-uniform circular array along with a phase reference antenna at the center of the array. Several quantities and parameters are studied, e.g., frequency behavior, origins of phase measurement errors, Signal to Noise Ratio (SNR) effect on phase measurement, and the effect of the phase measurement error on direction finding performance. The proposed interferometer is able to tolerate at least 35 degrees of phase measurement error. Radius of the array is determined to be 22 cm in order to have good frequency response in the desired frequency band. Both Generalized Regression Neural Network (GRNN) and Maximum Likelihood (ML) estimation are applied for mapping the phase relationships between antennas to the Direction of Arrival (DoA). The results of two methods are well matched, and therefore validation is performed.

1. , , Electronic Warfare and Radar Systems Engineering Handbook, revision 2, Naval Air Systems Command and Naval Air Warfare Center, Washington, D.C. 20361, 1999.

2. Wiley, R. G., ELINT: The Interception and Analysis of Radar Signals , Artech House, 2006.

3. Jacobs, E. and E. W. Ralston, "Ambiguity resolution in interferometry," IEEE Trans. on Aerospace and Electronic Systems, Vol. 17, No. 6, 766-780, 1981.
doi:10.1109/TAES.1981.309127

4. Lipsky, S., Microwave Passive Direction Finding, SciTech, 2004.

5. Suarez-Fajardo, C., M. Ferrando-Batallur, A. Valero-Nogueira, and V. Rodrigo, "Multiple beam system with circular arrays," Antennas and Propagation Society International Symposium, Vol. 4B, 35-38, 2005.

6. Suarez-Fajardo, C., M. Ferrando-Bataller, and A. Valero-Nogueira, "Pattern synthesis of uniform circular arrays with directive elements," Antennas and Propagation Society International Symposium, Vol. 3, 2812-2815, 2004.

7. Xun, Y. and Z.-Z. Cui, "Two-dimensional circular array real-time phase interferometer algorithm and its correction," 2nd International Congress Image and Signal Processing, 1-5, 2009.
doi:10.1109/CISP.2009.5304540

8. Mathews, C. P. and M. D. Zoltowski, "Eigenstructure techniques for 2-D angle estimation with uniform circular arrays," IEEE Transactions on Signal Processing, Vol. 42, 2395-2407, 1994.
doi:10.1109/78.317861

9. Ramos, J., C. P. Mathews, and M. D. Zoltowski, "FCA-ESPRIT: A closed-form 2-D angle estimation algorithm for filled circular arrays with arbitrary sampling lattices ," IEEE Transactions on Signal Processing, Vol. 47, No. 1, 213-217, Jan. 1999.
doi:10.1109/78.738255

10. Zhang, X., Y. Shi, and D. Xu, "Novel blind joint direction of arrival and polarization estimation for polarization-sensitive uniform circular array," Progress In Electromagnetics Research, Vol. 86, 19-37, 2008.
doi:10.2528/PIER08082302

11. Tan, C., P. Fletcher, M. Beach, A. Nix, M. Landmann, and R. Thoma , "On the application of circular arrays in direction finding. Part I: Investigation into the estimation algorithms," IEEE 1st Workshop on Opportunities of the Multidimensional Propagation Channel, 29-30, 2002.

12. El-Kassis, C., J. Picheral, and C. Mokbel, "EM-ESPRIT algorithm for direction finding with nonuniform arrays," IEEE 14th Workshop on Statistical Signal Processing, 453-457, 2007.
doi:10.1109/SSP.2007.4301299

13. Rubsamen, M. and A. B. Gershman, "Direction-of-arrival estimation for nonuniform sensor arrays: From manifold separation to ourier domain MUSIC methods," IEEE Transactions on Signal Processing, Vol. 57, No. 2, 588-599, 2009.
doi:10.1109/TSP.2008.2008560

14. Yasar, T. K. and T. E. Tuncer, "Wideband DOA estimation for nonuniform linear arrays with Wiener array interpolation," IEEE 5th Workshop on Sensor Array and Multichannel Signal Processing Workshop, 207-211, 2008.
doi:10.1109/SAM.2008.4606856

15. Rubsamen, M. and A. B. Gershman, "Root-music based direction-of-arrival estimation methods for arbitrary non-uniform arrays," IEEE International Conference on Acoustics, Speech and Signal Processing, 2317-2320, 2008.
doi:10.1109/ICASSP.2008.4518110

16. Du, K. L., A. K. Y. Lai, K. K. M. Cheng, and M. N. S. Swamy, "Neural methods for antenna array signal processing: A review," Elsevier Science Signal Processing, Vol. 82, No. 4, 547-561, 2002.

17. Demuth, H. and M. Beale, Neural Network Toolbox User's Guide, Version 4, MathWorks Inc., 2002.

18. Chen, Z., G. Gokeda, and Y. Yu, Introduction to Direction-of-arrival Estimation, Artech House, 2010.

19. Chandran, S., Advances in Direction-of-arrival Estimation, Aretch House, 2005.

Mr. Mohammad Ali Ebrahimi-Ganjeh

Dr. Mohammad Soltanian

Dr. Mehdi Salarpour

Dr. Amir Mansour Pezeshk