Direct measurement of laser aberration and ahead point from ARTEMIS satellite through strong clouds

Abstract

Laser communication has advances in compared with radio frequency communication as result of much high carrier frequency from ultraviolet to near infrared. Very narrow laser beam is possible to form with very high power density. But laser beam has high destruction and attenuation on clouds, turbulence, scattering on aerosols and molecules of the atmosphere. Low Earth orbits (LEO), Middling Earth orbits (MEO) and partly Geosynchronous Earth orbit (GSO) satellites moving on the sky and laser light from satellites moves across different turbulence conditions of the atmosphere, clouds, molecules of the atmosphere H2O, O2, N2, CO, O3 and other. We performed unique experiments with propagation of laser beams from beacon of OPALE terminal of ARTEMIS satellite through thin clouds. We have found that small part of laser radiation is received from ahead point there the satellite will be after time of propagation of laser radiation from the satellite to telescope. It is in accordance with theory of relativity for aberration of light during transition from moving to not moving coordinate systems. It is positive effect for laser communication through the atmosphere and clouds because will be possible to develop a system for reduce of the atmosphere turbulence during of laser communication from ground to the satellites. The interest is what will be during propagation of laser radiation from the satellite through strong clouds. The detail descriptions of laser experiment with ARTEMIS GSO satellite through strong clouds and estimations of the laser power through strong clouds are presented in this paper. Accordingly we must search the optimal wave lengths and power of lasers for performs laser communication in different cloudy conditions.