Research On Brillouin Scattering Spectra Of Atmospheric And Detection Technology

laser detection technology based on Brillouin scattering is not only a frontierresearch subject，but is the new direction of development of laser detection technologyin the future. Using Brillouin scattering technique can measure a variety ofatmospheric parameters such as temperature, pressure, gas density distribution, airvelocity, refractive index, air turbulence and so on. It has important potentialapplications in the atmospheric environmental monitoring, military, meteorological,air dynamics, aerospace and other fields.In view of the spontaneous Brillouin frequency shift dispersion of atmospherewhich under the normal conditions is very small. Brillouin and Rayleigh scatteringsignals are usually mixed together. It is difficult to accurately identified thespontaneous Brillouin and Rayleigh signals depend on current technology. But toobtain accurate Brillouin frequency shift is a key of using Brillouin scattering tomeasure the atmospheric parameters and application. Therefore, the S6theoreticalmodel was introduced in this paper. We have simulated spectrum shape characteristicsof Rayleigh-Brillouin scattering according to appropriate conditions from thetheoretical. It is can be to make up the resolution and accuracy of detection systemdeficiencies by qualitative and quantitative analysis of Brillouin frequency shiftcharacteristics between measured spectra and theoretical spectrum. In addition, inorder to carry out provide theoretical guidance for experimental study. We simulateBrillouin backscattering spectrum shape at different altitudes, different air pressure,temperature, and other atmospheric conditions, and analyzes internal factors whichcaused spectral shape of changes. The Simulation results show that: Brillouinscattering laser detection technique is more suitable for the detection of cryosphereatmosphere, using longer wavelength laser, can achieve higher resolution of theBrillouin spectrum.We have discussed the method of using narrow-band single-mode laser to detectthe atmospheric spectrum of spontaneous Brillouin scattering based on theory and model simulation, we have made with high spectral resolution Fabry-Perol directdetection of laser technology to design the experimental detection system in this paper.Although the error between experimental results and theoretical is larger, but thistechnology is feasible which has been confirmed through back180degree and90degree side scatter feasibility verification experiment exploration and research. In theend, this article not only discussed the problems encountered in the experiment andthe detection system defects, but analysis of cause of the problem, given specificprograms to solve problems and improve the system.The system that based on Brillouin backscattering in single beam laser directdetection not only with relatively simple structure, small volume and easy to installwhich compared to the other Brillouin scattering detection systems and programsother wise at homeland or abroad，but also having potential to development oflaser radar with different platforms. Besides, this system can be used to measurementby remote and real-time if combined with other electronic technology.