volume | PIER Journals

Abstract

The scattering characteristic of paraxial gaussian beam from two dimensional dielectric rough surfaces is studied in this paper. The modification of the Kirchhoff approximation theory for rough surface scattering by an incident gaussian beam instead of a plane wave are developed based on conventional Kirchhoff scattering theory and plane wave spectrum expansion method. The coherent and incoherent scattered intensity and cross section of two dimensional dielectric rough surfaces is derived in detail. As a application, under incidence wave length λ = 1.06 μm, we calculate the coherent and incoherent scattered intensity and cross section of Gaussian beam scattering from plating aluminium dielectric rough surfaces change with the scattering zenith angles in different rough surface correlation length, rough surface height root mean square and other conditions. In the same scattering conditions, we compare the coherent and incoherent scattered section between the gaussian beam and plane wave to prove that our methods and programming cods is correct. The numerical results are shown that the incident gaussian beam size is much larger compared with the surface height correlation length, the normalized scattering cross section is the same as for an incident plane wave. The ratio between the beam size and the surface height correlation length play an important role in the scattering characteristic of the gaussian beam from two dimensional dielectric rough surfaces. The ratio is bigger, the coherent and scattered intensity and section is more remarkable and on the contrary the incoherent scattered intensity and section is relatively smaller.

1. Tsang, L., J. A. Kong, and R. Shin, Theory of Microwave Remote Sensing, Wiley-Interscience, 1985.

2. Tsang, L., J. A. Kong, and K. H. Ding, Scattering of Electromagnetic Waves, Vol. 1, Theory and Applications, Wiley Interscience, 2000.

3. Tsang, L., J. A. Kong, K. H. Ding, and C. O. Ao, Scattering of Electromagnetic Waves, Vol. 2, Numerical Simulations, Wiley Interscience, 2001.

4. Tsang, L. and J. A. Kong, Scattering of Electromagnetic Waves, Vol. 3, Advanced Topics, Wiley Interscience, 2001.

5. Chen, H., Z. Wu, R. Yang, and L. Bai, "Gaussian beam scattering from arbitrarily shaped objects with rough surfaces," Waves in Random Media, Vol. 14, No. 3, 277-286, 2004.
doi:10.1088/0959-7174/14/3/005 Google Scholar

6. Wang, M.-J., Z.-S. Wu, Y.-L. Li, et al. "Modeling and measuring the pulse laser scattering echo power from whole dimension target," Chinese Journal of Lasers, Vol. 33, No. 11, 1557-1561, 2006. Google Scholar

7. Wu, Z. and S. Cui, "Bi-static scattering by arbitrarily shaped objects with rough surface at optical and infrared frequencies," Inter. J. of Infrared and Mill. Waves, Vol. 13, No. 4, 537-549, 1992.
doi:10.1007/BF01010711 Google Scholar

8. Bankman, I., "Analytical model of Doppler spectra of coherent light backscattered from rotating cones and cylinders," J. Opt. Soc. Am. A Opt., Vol. 17, No. 3, 465-476, 2000.
doi:10.1364/JOSAA.17.000465 Google Scholar

9. Dahl, M., "Electromagnetic Gaussian beams and Riemannian geometry," Progress In Electromagnetics Research, Vol. 60, 265-291, 2006.
doi:10.2528/PIER05122802 Google Scholar

10. Wu, Z. and L. Guo, "Electromagnetic scattering from a multilayered cylinder arbitrarily located in a Gaussian beam, a new recursive algorithms," Progress In Electromagnetics Research, Vol. 18, 317-333, 1998.
doi:10.2528/PIER97071100 Google Scholar

11. Collin, R. E., "Scattering of an incident Gaussian beam by a perfectly conducting rough surface," IEEE Trans. on Antennas Propagat., Vol. 42, No. 1, 70-74, 1994.
doi:10.2528/PIER96042200 Google Scholar

12. Shen, T., W. Dou, and Z. Sun, "Gaussian beam scattering from a semicircular channel in a conducting plane," Progress In Electromagnetics Research, Vol. 16, 67-85, 1997. Google Scholar

13. Chen, H., Scattering of Gaussian beam by object with rough surface and its application on laser one-dimensional range profile, A doctoral dissertation, Xidian University, 2005.

14. Xue, Q. Z., Z. S.Wu, and Y. Yang, "The scattering characteristics of Gaussian beam from dielectric rough surfaces," Journal of Electronics, Vol. 22, 875-880, 2000.
doi:10.2528/PIER05090702 Google Scholar

15. Chabory, A., J. Sokoloff, and S. Bolioli, "Novel Gabor-based Gaussian beam expansion for curved aperture radiation in dimension two," Progress In Electromagnetics Research, Vol. 58, 171-185, 2006. Google Scholar

16. Carter, W. H., "Electromagnetic field of a Gaussian beam with an Elliptical cross section," J. Opt. Soc. Am., Vol. 62, No. 10, 1195-1201, 1972. Google Scholar

17. Ulaby, F. T., Microwave Remote Sensing Active and Passive, Vol. 2, Addi-son-Wesley, 1982.

18. Collin, R. E., Antennas and Radio Wave Propagation, McGraw Hill, 1985.
doi:10.1121/1.396188

19. Thoros, E. L., "The validity of the Kirchhoff approximation for rough surfaces scattering using a gaussian roughness spectrum," J. Acoust. Soc. Am., Vol. 83, No. 1, 78-92, 1988. Google Scholar

20. Fung, A. K. and M. F. Chen, "Numerical simulation of scattering from simple and compo-site random surfaces," J. Opt. Soc. Am., Vol. 2, 74-84, 1985.
doi:10.1029/94RS00511 Google Scholar

21. Li, L., C. H. Chan, and L. Tsang, "Numerical simulation of conical diffraction of tapered electromagnetic waves from random rough surfaces and applications to passive remote sensing," Radio Science, Vol. 29, 587-598, 1994.
doi:10.1364/JOSAA.16.000176 Google Scholar

22. Toporkov, J. V., R. S. Awadallah, and G. S. Brown, "Issues related to the use of a Gaussian-like incident field for low-grazing-angle scattering," J. Opt. Soc. Am. (A), Vol. 16, 176-187, 1999. Google Scholar

Professor Ming-Jun Wang

Prof. Zhen-Sen Wu

Professor Ying-Le Li