Modified Physical Optics Approximation for RCS Calculation of Electrically Large Objects with Coated Dielectric

Document Type: Research Paper

Authors

Department‎ of Electrical and Computer Engineering‎, ‎Isfahan University of Technology (IUT)‎, ‎Isfahan‎, ‎Iran

Abstract

The Radar Cross Section of a target plays an important role in the detection of targets by radars‎. ‎This paper presents a new method to predict the bistatic and monostatic RCS of coated electrically large objects. ‎The bodies can be covered by lossy electric and/or magnetic Radar Absorbing Materials (RAMs)‎. ‎These materials can be approximated by the Fresnel reflection coefficients‎. ‎The proposed method uses modified Physical Optics (PO) approximation to obtain the object scattered field‎. ‎One of the advantages is the use of Stationary Phase Method (SPM) to solve the PO integral‎. This is because‎‎the SPM reduces significantly the computation time required to solve this integral as compared to  rigorously numerical integration techniques‎. ‎Simulationresults are presented to verify the accuracy and efficiency of the proposed method. The results are compared with commercial FEKO and CST software in order to show its superiority as far as the computation time is concerned.

Keywords


[1] M. F. Catedra, C. Delgado, and I. G. Diego, "New physical optics approach for an efficient treatment of multiple bounces in curved bodies defined by an impedance boundary condition," IEEE Transactions on Antennas and Propagation, vol. 56, no. 3, pp. 728-736, 2008.

[2] F. S. de Adana, I. G. Diego, O. G. Blanco, P. Lozano, and M. F. Catedra, "Method based on physical optics for the computation of the radar cross section including diffraction and double effects of metallic and absorbing bodies modeled with parametric surfaces," IEEE Transactions on Antennas and Propagation, vol. 52, no. 5, pp. 3295-3303, 2004.

[3] J. T. Hwang, S. Y. Hong, J. H. Song, and H. W. Kwon, "'Radar cross section analysis using physical optics and its applications to marine targets," Journal of Applied Mathematics and Physics, vol. 3, pp. 166-171, 2015.

[4] F. Weinmann, "The Influence of Surface Curvature on HighFrequency RCS Simulations" The Second European Conference on Antennas and Propagation EuCAP, Edinburgh, pp. 1-5, Nov. 2007.

[5] C. Corbel, C. Bourlier, N. Pinel, and J. Chauveau, "Rough Surface RCS Measurements and Simulations Using the Physical Optics Approximation" IEEE Trans. Antennas Propag., vol. 61, no. 10, pp. 5155-5165, 2013.

[6] F. Weinmann, "Ray tracing with po/ptd for rcs modeling of large complex objects," IEEE Trans. Antennas and Propaation., vol. 54, no. 6, pp. 1797-1806, 2006.

[7] Y. An, D. Wang, R. Chen, "Improved multilevel physical optics algorithm for fast computation of monostatic radar cross section," IET Microwaves, Antennas & Propagation, vol. 8, no. 2, pp. 93-98, 2014.

[8] H. Mohammadzadeh, A. Zeidaabadi-Nezhad, and Z. H. Firouzeh, "Modified physical optics approximation and physical theory of diffraction for rcs calculation of dielectric coated pec," Antennas and Propagation Society International Symposium (APSURSI), Orlando-FL, pp. 1896 – 1897, 2013.

[9] A. Noga, "Physical optics approximation for PEC objects coated with lossy material," 21st International Conference in Radioelektronika 2011, pp. 1-3, 2011.

[10] W. C. Gibson, The Method of Moments in Electromagnetics, Chapman & Hall/CRC and Taylor & Francis Group, 2008. [11] X. J. Chen , X. W. Shi "Comments on a formulation in radar cross section," Journal of Electromagnetic Waves and Applications, vol. 21, no. 15, p. 2389-2394, 2007.

[12] J. J. Stamnes, Waves in Focal Region, IOP Publisher, 1986.

[13] L. P. Felsen, N. Marcuvitz, Radiation and Scattering of Waves, IEEE Press, 1994.

[14] J. Perez, M. F. Catedra, "Application of physical optics to the RCS computation of bodies modeled with NURBS surfaces," IEEE Transactions on Antennas and Propagation, vol. 42, no. 10, pp. 1404-1411, 1994.

[15] P. C. Lash, "Comparison of computational electromagnetic codes for prediction of low-frequency radar cross section," Master of Science, Department of Electrical and Computer Engineering, Air Force Institute of Technology, 2006.

[16] L. M. Brekhovskikh, Waves in Layered Media, 2nd ed., vol. 6, Academic Press, 1960.

[17] R. S. Elliott, Antenna Theory and Design, 2nd ed., IEEE Press, 2003.

[18] C. A. Balanis, Advanced Engineering Electromagnetics, 2nd ed., John Wiley & Sons, 2012.

[19] D. Klement, J. Preissner, and V. Stein, "Special problems in applying the physical optics method for backscatter computations of complicated objects," IEEE Transactions on Antennas and Propagation, vol. 36, no. 2, pp. 228-237, 1988.