The new type of remote spectrometer on the basis of multifrequency pulse - periodic NH_3- and DF- lasers gives possibility to overcome the problem of turulence induced scintillation noise. The lasers readiate in atmospheric windows of transparency. NH_3-laser emits in absorption spectral region of majority of composite organic and inorganic pollutants (ammonia, freons, chlorides, - about 200 detectable substances in all), and the DF-laser - of common industrial pollutants (SO_2, NO_x, H_2S, etc.). DF-laser emits in a maximum of scattering on aerosols, while NH_3- the laser is practically insensitive to them, this enables to monitor the aerosol component as well. The key difference is simultaneous emission and detection of a multifrequency laser radiation. NH_3- laser can radiate in single pulse 10-20 lines simultaneously, and DF-laser - 15-21 lines with time delay of tens nanoseconds. The multifrequency pulse mode enables to overcome practically completely the influence of atmospheric turbulence and to reach 30-40 times increase of accuracy in comparison with sequential switching of laser lines. Thus it makes possible not only to solve the traditional task of a determination of some given admixture, and much more exactly, but also to determine complexly a state of the atmosphere (temperature, dampness, turbulence, determination of several impurities and aerosols). New algorithm for data evaluation was elaborated. Extensive modeling of the system was fulfilled. Laboratory and the field tests of the device on 0,4 km trace had been conducted. It was shown, that there is a considerable reserve in sensitivity of the device.
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