6. Computer methods for processing signals and images

G. P. Arumov, A. V. Bukharin, A. V. Turin
Space Research Institute Russian Academy of Science, Russia

Nephelometr modes using hardware correction of the return signal for the problem of determining the lidar ratio on the open trace

Nephelometer with pulsed laser operation mode (LIDAR), a rectangular shape with a mode (linear correction feedback signal) with a triangular pulse mode (inverse quadratic correction signal) is Paper ID: 5-2 240 considered. For these modes, there are two possibilities for the local analog calibration. In the first case, a ratio of the signals in the linear and quadratic correction of signal. The second ratio of the signals in linear correction mode and lidar mode. In this case, the trace of the ratio backscattering signal is linear in both cases. The advantage of the first mode compared to the second mode in the measurement of extinction coefficient. When calibrating the measuring backscatter coefficient has the advantage of the quadratic correction because it requires minimal use of attenuating filters. Proposed indicator of the degree of homogeneity of the trace. This indicator is the simultaneous measurement of the value of extinction coefficient using these two modes nephelometer. For inhomogeneous atmosphere measured values of extinction coefficients will be different. To measure the geometric distortion of the probe beam should use an additional receiving channel. The ratio of return signals on the secondary and main receiver channels in the presence of a local calibration is an indicator of the distortion of the probe beam. Nephelometer mode is effective tool for determining the lidar ratio because of simultaneous measurement of the backscatter coefficient and extinction coefficient.
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