In the view of measuring directional fluctuations of a thin laser beam sent through a heated turbulent jet, an optical method using interference and diffraction with the out coming beam is proposed. The experimental set-up is described. A new technique for separating directional fluctuations of the laser beam is explained. From the measurement of the interference pattern perturbations, are deduced the Rms of the laser beam deflection angle, the spectrum of directional fluctuations of the laser beam, and the value of a scattering coefficient characterizing the heated turbulent jet. The measured spectrum reveals a -8/3 power law and the value obtained for that coefficient is nearly equal to that found in previous works. This agreement enables to conclude that the experimental technique used is efficient and satisfactory.
Elisabeth Ngo Nyobe,
"Experimental Technique Using an Interference Pattern for Measuring Directional Fluctuations of a Laser Beam Created by a Strong Thermal Turbulence," Progress In Electromagnetics Research,
Vol. 84, 289-306, 2008. doi:10.2528/PIER08072803
1. Chernov, L. A., Wave Propagation in a Random Medium, McGraw-Hill, New York, 1960.
2. Shwetanshumala, S., S. Jana, and S. Konar, "Propagation of a mixture of modes of a laser beam in a medium with saturable nonlinearity," Journal of Electromagnetic Waves and Applications, Vol. 20, No. 1, 65-77, 2006. doi:10.1163/156939306775777422
3. Tatarskii, V. I., Wave Propagation in a Turbulent Medium, McGraw-Hill, New York, 1961.
4. Tatarskii, V. I., The Effects of the Turbulent Atmosphere on Wave Propagation, US Department of Commerce, National Technical Information Service TT-68-50464, 1971.
5. Popov, A. V. and V. V. Kopeikin, "Electromagnetic pulse propagation over nonuniform earth surface: Numerical simulation," Progress In Electromagnetics Research B, Vol. 6, 37-64, 2008.
6. Klyatskin, V. I. and V. I. Tatarskii, "Statistical theory of light propagation in turbulent medium (Review)," Radiofizika, Vol. 15, No. 10, 1433-1455, 1972.
7. Ngo Nyobe, E. and E. Pemha, "Propagation of a laser beam through a plane and free turbulent heated air flow: Determination of the stochastic characteristics of the laser beam random direction and some experimental results," Progress In Electromagnetics Research, Vol. 53, 2005.
8. Ngo Nyobe, E. and E. Pemha, "Shape optimization using genetic algorithms and laser beam propagation for the determination of the diffusion coefficient in a hot turbulent jet of air," Progress In Electromagnetics Research B, Vol. 4, 211-221, 2008.
9. Ishimaru, A., Wave Propagation and Scattering in Random Media, 1 and 2, Academic Press, New York, 1978.
10. Clifford, S. F., "The classical theory of wave propagation in a turbulent medium," Laser Beam Propagation in the Atmosphere, J. W. Strohbehn, ed., Topics in Applied Physics, Vol. 25, 9-43, 1978.
11. Hernandez-Lopez, M. A. and M. Quintillan-Gonzales, "A finite element method code to analyse waveguide dispersion," Journal of Electromagnetic Waves and Applications, Vol. 21, No. 3, 397-408, 2007. doi:10.1163/156939307779367396
12. Sirazetdinov, V. S., A. D. Starikov, and D. H. Titterton, "Study of laser beam propagation through a jet aircraft engines exhaust," Proceedings of SPIE, Vol. 4167, 120-129, 2001. doi:10.1117/12.413815
13. Shapiro, A. R., "Laser propagation in aircraft wakes," SPIE 2005, 139-154, 1993.
14. Lonappan, A., G. Bindu, V. Thomas, J. Jacob, C. Rajasekaran, and K. T. Mathew, "Diagnosis of diabetes mellitus using microwaves," Journal of Electromagnetic Waves and Applications, Vol. 21, No. 10, 2007. doi:10.1163/156939307783239429
15. Zainud-Deen, S. H., W. M. Hassen, E. M. Ali, and K. H. Awadalla, "Breast cancer detection using a hybrid finite difference frequency domain and particle swarm optimization techniques," Progress In Electromagnetics Research B, Vol. 3, 35-46, 2007.
16. Talaat Ibrahim, A., "Using microwave energy to treat tumours," Progress In Electromagnetics Research B, Vol. 3, 1-27, 2007.
17. Guo, B., Y. Weng, J. Li, P. Stoica, and R. Wu, "Microwave imaging via adaptive beamforming methods for breast cancer detection," Journal of Electromagnetic Waves and Applications, Vol. 20, No. 1, 2007.
18. Wu, B.-I., F. C. Cox, and J. A. Kong, "Experimental methodology for non-thermal effects of electromagnetic radiation on biologics," Journal of Electromagnetic Waves and Applications, Vol. 21, No. 4, 533-548, 2007. doi:10.1163/156939307780616829
19. Lu, Z. Y., H. Ding, W. Q. Sun, and P. P. Shi, "The study on experiment and mechanism of sterilization with electromagnetic waves," Journal of Electromagnetic Waves and Applications, Vol. 21, No. 6, 729-735, 2007.
20. Nghiem, S. V., M. Borgeaud, J. A. Kong, and R. T. Shin, "Polarimetric remote sensing of geophysical media with layer random medium model," Progress In Electromagnetics Research, Vol. 03, 1-73, 1990.
21. Shin, R. T. and J. A. Kong, "Radiative transfer theory for active remote sensing of two-layer random medium," Progress In Electromagnetics Research, Vol. 01, 359-417, 1989. doi:10.2528/PIER02032501
22. Angot, L., H. Roussel, and W. Tabbara, "A full wave three dimensional analysis of forest remote sensing using VHF electromagnetic wave," Progress In Electromagnetics Research, Vol. 38, 311-331, 2002. doi:10.1163/156939307779367350
23. Wang, C. J., B. Y. Wen, Z. G. Ma, W. D. Yan, and X. J. Huang, "Measurement of river surface currents with UHF FMCW radar systems," Journal of Electromagnetic Waves and Applications, Vol. 21, No. 3, 375-386, 2007. doi:10.2528/PIER07030101
24. Atteia, G. E., A. A. Shaalan, and K. A. Hussein, "Wideband partially-covered bowtie antenna for ground-penetrating-radars," Progress In Electromagnetics Research, Vol. 71, 211-226, 2007.
25. Mead, J. B. and R. E. McIntosh, "Millimeter-wave polarimetric radars," Progress In Electromagnetics Research, Vol. 03, 391-450, 1990.
26. Ojo, J. S., M. O. Ajewole, and S. K. Sarkar, "Rain rate and rain attenuation prediction for satellite communication in Ku and Ka bands over Nigeria," Progress In Electromagnetics Research B, Vol. 5, 207-223, 2007.
27. Titterton, D. H., "A review of optical countermeasures," Proceedings SPIE Conference on Technologies for Optical Countermeasures, Vol. 5615, 1-15, London, 2004.
28. Titterton, D. H., "The development of infrared countermeasure technology and systems," Mid IR Semiconductor Optronic, A. Krier (ed.), Springer-Verlag, 2005. doi:10.1088/0959-7174/1/3/002
29. Consortini, A. and K. A. O'Donnell, "Beam wandering of thin parallel beams through atmospheric turbulence," Waves in Random Media, Vol. 3, S11-S28, 1991.
30. Innocenti, C. and A. Consortini, "Monitoring evolution of laser atmospheric scintillation statistics by use of fractional moments," Journal of Modern Optics, Vol. 49, No. 13, 2002. doi:10.1088/0959-7174/7/2/001
31. Joia, I. A., et al., "Intensity fluctuations in a laser beam due to propagation through a plane turbulent jet," Waves in Random Media, Vol. 7, 169-181, 1997.
32. Ivanova, I. V., D. I. Dimitriev, and V. S. Sirazetdinov, "Probability density of intensity fluctuations for laser beams disturbed by turbulent aero-engine exhaust," Lasers for Measurements and Information Transfer, Proceedings of SPIE, Vol. 6594, 2007.
33. Born, M. and E. Wolf, Principles of Optics: Electromagnetic Theory of Propagation, Interference and Diffraction of Light, 7th Ed., Cambridge University Press, Cambridge, 1999.