With rapid development of satellite technology in monitoring the ocean, a good understanding of the physical processes involved in the electromagnetic ocean-surface interaction is required. The composite surface models are usually applied in the analysis of the interaction, hence a systematical check of their region of validity is desirable. Based on a generalized minimal residual procedure which is right preconditioned (GMRES-RP) that we have recently developed which has demonstrated the desirable properties of a numerical algorithm: robust and efficient, in this paper, for bistatic scattering from one dimensional ocean surfaces, we carry out a systematic assessment of the performance of the popular two-scale model and the advanced three-scale model under different conditions of ocean surface wind speeds, polarizations, frequencies, and incidence angles. It is found that the two-scale model in general captures the bistatic scattering pattern, yet the accuracy of geometrical optics (GO) for the large scale wave brings considerable impact on the overall accuracy. If the evaluation of the contribution of the large scale wave is instead using direct numerical integration for the corresponding Kirchhoff integral, impressive improvements are frequently observed, especially at low frequency (L and C bands) and low wind speed (3 m/s). But care should be taken when apply two-scale method with numerical integration, since there are cases where visible discrepancy with method of moment (MoM) are observed. On the other hand, the three-scale model is found in very good agreement with MoM across the considered ocean surface wind speeds, polarizations, frequencies, and incidence angles, hence represents a much advanced model over the two-scale model.
2. Gaiser, P. W., , et al., "The WindSat spaceborne polarimetric microwave radiometer: Sensor description and early orbit performance," IEEE Trans. Geosci. Remote Sens., Vol. 42, No. 11, 2347-2361, 2004.
doi:10.1109/TGRS.2004.836867
3. Wright, , J. W., "A new model for sea clutter," IEEE Trans. Antennas Propag., Vol. 16, No. 2, 217-223, 1968..
doi:10.1109/TAP.1968.1139147
4. Lyzenga, , D. R. , J. F. Vesecky, and , "Two-scale polarimetric emissivity model: E±ciency improvements and comparisons with data," Progress In Electromagnetics Research,, Vol. 37, 205-219, 2002..
doi:10.2528/PIER02101000
5. Soriano, , G. , M. Saillard, and , "Modelization of the scattering of electromagnetic waves from the ocean surface," Progress In Electromagnetics Research, Vol. 37, 101-128, 2002.
doi:10.2528/PIER01111800
6. Vaitilingom, , L. , A. Khenchaf, and , "Radar cross sections of sea and ground clutter estimated by two scale model and small slope approximation in HF-VHF bands," Progress In Electromagnetics Research B,, Vol. 29, 311-338, 2011.
doi:10.2528/PIERB11021607
7. Plant, , W. J., , "A stochastic, multiscale model of microwave backscatter from the ocean," J. Geophys. Res., Vol. 107, No. C9, 3120, 2002.
doi:10.1029/2001JC000909
8. Romeiser, , R.,s, A. Schmidt, and W. Alpers,s, "A three-scale composite surface model for the ocean wave-radar modulation transfer function," J. Geophys. Res., Vol. 99, No. C5, 9785-9801, 1994.
doi:10.1029/93JC03372
9. Banks, , C. J., , C. P. Gommenginger, M. A. Srokosz, and H. M. Snaith, "Validating SMOS ocean surface salinity in the Atlantic with Argo and operational ocean model data," IEEE Trans. Geosci. Remote Sens., Vol. 50, No. 5, 1688-1702, 2012.
doi:10.1109/TGRS.2011.2167340
10. Guimbard, , S., , J. Gourrion, M. Portabella, A. Turiel, C. Gabarro and J. Font, "SMOS semi-empirical ocean forward model adjustment," IEEE Trans. Geosci. Remote Sens., Vol. 50, No. 5, 1676-1687, 2012.
doi:10.1109/TGRS.2012.2188410
11. Wu, , Z.-S., , J.-P. Zhang, L.-X. Guo, and P. Zhou,s, "An improved two-scale model with volume scattering for the dynamic ocean surface," Progress In Electromagnetics Research, Vol. 89, 39-56, 2009.
doi:10.2528/PIER08111803
12. Sajjad, , N., A. Khenchaf, A. Coatanhay, and A. Awada,s, "An improved two-scale model for the ocean surface bistatic scattering, ," IEEE Trans. Geosci. Remote Sens. Symposium, Vol. 1, I387-I390, 2008.
13. Voronovich, , A. G., "Small-slope approximation for electromagnetic wave scattering at a rough interface of two dielectric half-spaces," Waves Random Media, Vol. 4, No. 3, 337-367, 1994.
doi:10.1088/0959-7174/4/3/008
14. Yang, , G., Y. Du, and , "A robust preconditioned GMRES method for electromagnetic scattering from dielectric rough surfaces," IEEE Trans. Geosci. Remote Sens., Vol. 50, No. 9, 3396-3408, 2012.
doi:10.1109/TGRS.2012.2184291
15. Holliday, , D., , L. L. DeRaad, and G. J. St-Cyr, "Forward-backward: A new method for computing low-grazing angle scattering," IEEE Trans. Antennas Propag., Vol. 44, No. 5, 722-729, 1996..
doi:10.1109/8.496263
16. Chou, H. T. and J. T. Johnson, "A novel acceleration algorithm for the computation of scattering from rough surfaces with the forward-backward method," Radio Sci.,, Vol. 33, 1277-1288, 1998..
doi:10.1029/98RS01888
17. Torrungrueng, , D., J. T. Johnson, and H. T. Chou, "Some issues related to the novel spectral acceleration method for the fast computation of radiation/scattering from one-dimensional extremely large scale quasi-planar structures," Radio Sci., Vol. 37, No. 2, 1019, 2002.
doi:10.1029/2000RS002504
18. Li, , S.-Q., , C. H. Chan, L. Tsang, and L. Zhou, "Microwave emission of rough ocean surfaces with full spatial spectrum based on the multilevel expansion method," IEEE Trans. Geosci. Remote Sens., Vol. 40, No. 3, 574-582, 2002..
doi:10.1109/TGRS.2002.1000317
19. Gill, , E., , W. Huang, and J. Walsh, , "The effect of the bistatic scattering angle on the high-frequency radar cross sections of the ocean surface," IEEE Geosci. Remote Sens. Lett., Vol. 5, No. 2, 143-146, 2008.
doi:10.1109/LGRS.2008.915594
20. Ji, W.-J. , C.-M. Tong, and , "Bistatic scattering from two-dimensional dielectric ocean rough surface with a PEC object partially embedded by using the G-SMCG method," Progress In Electromagnetics Research, Vol. 105, 119-139, 2010.
doi:10.2528/PIER10041101
21. Chen, , H., , M. Zhang, and H.-C. Yin, "Facet-based treatment on microwave bistatic scattering of three-dimensional sea surface with electrically large ship," Progress In Electromagnetics Research, Vol. 123, 385-405, 2012.
doi:10.2528/PIER11101108
22. Tsang, , L., , J. A. Kong, and K. H. Ding, , Scattering of Electromagnetic Waves: Theories and Applications, John Wiley, 2000.
doi:10.1002/0471224286
23. Johnson, , J. T., , R. T. Shin, J. A. Kong, L. Tsang, and K. Pak, "A numerical study of the composite surface model for ocean backscattering ," IEEE Trans. Geosci. Remote Sens., Vol. 36, No. 1, 72-83, 1998.
doi:10.1109/36.655319
24. Johnson, , J. T., "A numerical study of low-grazing-angle backscatter from ocean-like impedance surfaces with the canonical grid method," IEEE Trans. Antennas Propag., Vol. 46, No. 1, 114-120, 1998.
doi:10.1109/8.655458
25. Elfouhaily, , T., , B. Chapron, K. Katsaros, and D. Vandemark, "A unified directional spectrum for long and short wind-driven waves," J. Geophys. Res., Vol. 102, No. C7, 781-769, 1997.
doi:10.1029/97JC00467
26. Thorsos, , E. I., , "Acoustic scattering from a `Pierson{Moskowitz' sea surface," J. Acoust. Soc. Am., , Vol. 88, No. 1, 335-349, 1990.
doi:10.1121/1.399909
27. Durden, S. , "A physical radar cross-section model for a wind-driven sea with swell," IEEE J. Ocean. Eng., Vol. 10, No. 4, 445-451, 1985..
doi:10.1109/JOE.1985.1145133
28. Bjerkaas, , A. W. , F. W. Riedel, and , "Proposed model for the elevation spectrum of a wind-roughened sea surface," DTIC Document, Tech. Rep., 1979.
29. Ulaby, F. T., R. K. Moore, and A. K. Fung, , "Microwave Remote Sensing: Active and Passive, Volume II: Radar Remote Sensing and Surface Scattering and Emission Theory," Artech House, , 1986.
30. Kasilingam, , D. P., O. H. Shemdin, and , "The validity of the composite surface model and its applications to the modulation of radar backscatter," Int. J. Remote Sensing, Vol. 13, No. 11, 2079-2104, 1992.
doi:10.1080/01431169208904255
31. Li, , Y. , J. C. West, and , "Low-grazing-angle scattering from 3-D breaking water wave crests," IEEE Trans. Geosci. Remote Sens.,, Vol. 44, No. 8, 2093-2101, 2006..
doi:10.1109/TGRS.2006.872129
32. McDaniel, , S. T., "Small-slope predictions of microwave backscatter from the sea surface," ," Waves Random Media, Vol. 11, No. 3,, Vol. 11, No. 3, 343-360, 2001.