<title>Determination of the lidar geometric factor for step apertures</title>

Abstract

An exact analytic description of the lidar geometric factor in the form of an integral of a product of the Bessel functions has been given within the framework of the small-angle approximation. A method for representing the lidar geometric factor in terms of elementary functions has been suggested. The behavior of the geometric factor on a sensing path has been analyzed for separated source and receiver.To solve inverse problems of lidar sensing of dense media, relative contributions of singly and multiply scattered components to a lidar return signal should be exactly estimated.1 Among the factors that govern the behavior of the ratio between the singly and multiply scattered components, the geometric factor should be first mentioned, which contains information about the effect of the parameters of lidar sensing geometry on the magnitude of a singly scattered signal.Proceeding from the small-angle approximation, an exact analytic integral expression for the lidar geometric factor has been derived in the present paper. A method for representing the geometric factor in terms of elementary functions has been described. The behavior of the factor on a sensing path has been studied for separated source and receiver.

<title>Effect of the instrumental function on measurements of phase functions of scattering by large particles at small scattering angles</title>

“…(6) describes the i radiance of attenuated incident light and the second term Is, (n1 , z) = B(10 * *x)(n1 ) (7) describes the radiance of singly scattered light and represents the convolution of the scattering phase function x(n1) with the radiance in the free space 10(n1). Formula (7) describes the law of transformation of the scattering phase function x(n1) in a measuring device as a function of the characteristics of the illuminating light beam.…”

“…Formulas (20) can be used to calculate the component of a measurable signal caused by the directly transmiued portion of the incident radiation. Results of calculations of the function H(y) were presented earlier 7. The second term in Eq.…”