On ratio between the specular and bragg components scattered by the quasi-gaussian sea surface

1Zapevalov, AS, 2Pokazeev, KV, 1Pustovoitenko, VV
1Marine Hydrophysical Institute of the National Academy of Sciences of Ukraine, Sevastopol, AR Crimea, Ukraine
2Lomonosov Moscow State University, Moscow, Russia
Kosm. nauka tehnol. 2006, 12 ;(5-6):023-029
Publication Language: Russian
The ratio between the specular and Bragg components in the reflected radio signal is analysed on the basis of well-known models for scattering and measurement data of sea surface slopes. The measurements were carried out from the Black Sea oceanographic platform with the use of a 2D-slope meter. It is shown that when radiosounding the sea surface, sea surface slope distribution deviation from the Gaussian distribution appear mainly at radio-wave incidence of up to 15°. Taking into account the quasi-Gaussian character of slope distribution leads to a change in the incidence domain, in which the specular component dominates the Bragg component by 1...2".
Keywords: 2D-slope meter, radiosounding, specular and bragg components
1. Bass F. G., Fuks I. M. Wave Scattering from Statistically Rough Surfaces, 424 p. (Nauka, Moscow, 1972) [in Russian].
2. Galaev Yu. M., Bol'shakov A. N., Efimov V. B., et al. Certain characteristics of the sea surface radar reflection at the quasi-verticsl angles of incidence: Preprint No. 1, MGI AN USSR, 24 p. (Sevastopol', 1978) [in Russian].
3. Zapevalov A. S. Variability of the sea surface local slopes characteristics. Prikladnaja gidromehanika, 7 (79), No. 1, 17—21 (2005) [in Russian].
4. Zapevalov A. S., Pokazeev K. V. Monitoring the state of the sea surface by means of laser sounding. In: Physical Problems of Ecology. (Environmental Physics): 4th All-Russian Conf., No. 12, 200—212 (Moscow, 2004) [in Russian].
5. Zapevalov A. S., Ratner Y. B. Analytic model of the probability density of slopes of the sea surface. Morskoj gidrofiz. zhurn., No. 2, 3—17 (2003) [in Russian].
6. Zubkovich S. G. Statistical characteristics of radio signals reflected from the earth's surface, 224 p. (Sovetskoe radio, Moscow, 1968) [in Russian].
7. Isakovich M. A. Wave scattering from a statistically rough surface. Zhurn. jeksperim. i teoret. fiziki, 23 (3), 305—314 (1952) [in Russian].
8. Kalmykov A. I., Kurekin A. S., Lementa Iu. A., Pustovoitenko V. V. Some features of backscattering of radio waves by sea surface at small grazing angles: Preprint No. 40, IRE AN USSR, 38 p. (Kharkov, 1974) [in Russian].
9. Kalmykov A. I., Kurekin A. S., Lementa Yu. A., et al. Peculiarities of scattering of microwave radiation by attacked sea waves. Izv. vuzov. Radiofizika, 19 (9), 1315—1321 (1976) [in Russian].
10. Kalmykov A. I., Lementa Yu. A., Ostrovsky I. E., et al. Energy scattering characteristics of the radio waves of the VHF range of the agitated sea surface: Preprint No. 71, IRE AN USSR, 60 p. (Kharkov, 1976) [in Russian].
11. Kalmykov A. I., Rozenberg A. D., Zeldis V. I. Backscattering of sound and radio waves by irregular ripples. Izv. vuzov. Radiofizika, 10 (6), 797—802 (1967) [in Russian].
12. Kendall M. J., Stewart A. The theory of distributions, 587 p. (Nauka, Moscow, 1966) [in Russian].
13. Kravtsov Yu. A., Mityagina M. I., Churyumov A. N. Non-resonant mechanism of scattering of electromagnetic waves on the sea surface: scattering on a steep sharp waves. Izv. vuzov. Radiofizika, 42 (3), 240—254 (1999) [in Russian].
14. Kudryavtsev V. N., Malinovsky V. V. Contribution of specular reflection to radar images of the sea surface. Issledovanie Zemli iz Kosmosa, No. 3, 3—11 (2004) [in Russian].
15. Feinberg E. L. Propagation of Radiowaves Along the Earth's Surface, 545 p. (Izd. Akad. Nauk SSSR, Moscow, 1961) [in Russian].
16. Khristoforov G. N., Zapevalov A. S., Babii M. V. Statistical characteristics of sea-surface slope at various wind speeds. Okeanologiya, 32 (3), 452—459 (1992) [in Russian].
17. Khristoforov G. N., Zapevalov A. S., Babii M. V. Measurements of sea surface roughness parameters in the transition from calm to wind waves. Izv. AN SSSR. Fizika atmosfery i okeana, 28 (4), 424—431 (1992) [in Russian].
18. Bass F. G., Fuks I. M., Kalmykov A. I., et al. Very High Frequency Radiowave Scattering by a Disturbed Sea Surface, Parts I and II. IEEE Trans. Antennas and Propag., AP-16, 554—568 (1968). 
19. Cox C., Munk W. Measurements of the roughness of the sea surface from photographs of the sun glitter. J. Opt. Soc. Amer., 44 (11), 838—850 (1954). 
20. Hughes B. A., Grant H. L., Chappell R. W. A fast response surface-wave slope meter and measured wind-waves components. Deep-Sea Res., 24 (12), 1211 — 1223 (1977). 
21. Kalmykov A. I., Pustovoytenko V. V. On polarization features of radiosignals scattered from the sea surface at small grazing angles. J. Geophys. Res., 81 (11), 1961 —1964 (1976).
22. Kudryavtsev V., Hauser D., Caudal G., et al. A semi-empirical model of the normalized cross-section of the sea surface. 1. Background model. J. Geophys. Res., 108C (3), FET2 1-24 (2003).
23. Longuet-Higgins M. S. On the skewness of sea-surface slopes. J. Phys. Oceanogr., 12, 1283— 1291 (1982).
24. Stoffelen A., Anderson D. Scatterometer data interpretation: Derivation of the transfer function CMOD4. J. Geophys. Res., 102C (3), 5767—5780 (1997). 
25. Valenzuela G. Theories for the interaction of electromagnetic and ocean waves. A Review. Boundary Layer Meteorology, 13 (1-4), 61—85 (1978). 
26. Wright J. W. A new model for sea clutter. IEEE Trans. Antennas and Propag., AP-16, 217—223 (1968).