A.N. Karhov

For many practical problems of laser sounding of spacecraft on the large distances there is a necessity to provide certain level of irradiation of a spacecraft by laser pulses. Generally the beam axis tests casual deviations from a spacecraft, the promptings of a beam caused by system errors and by influence of turbulent atmosphere that leads to changes of level of an exposition in a range from zero to the maximum value reached in the centre of a beam. For Gaussian beam and for normally distributed casual deviations of its axis analytical expressions for density of distribution of level of exposition spacecraft for cases of two-dimensional and one-dimensional deviations of a beam are received at absence, and also in the presence of regular deviations of its axis. The received dependences allow to estimate probability of irradiation of a spacecraft with the given threshold level of exposition at the set parametres of casual deviations us of a beam, divergence and power of a laser beam and can be used for optimization of the system of laser sounding spacecraft.