CONTENTS

Annex 1
�1���� Introduction
�2���� Absorption losses
�3���� Scattering losses
������� 3.1���� Attenuation of the transmitted signal due to Mie scattering
������� 3.2���� Increases in background noise due to Rayleigh scattered solar energy
�4���� Effects of turbulence on systems operating between 20 THz and 375 THz
������� 4.1���� Amplitude scintillation
����������������� 4.1.1���� Amplitude scintillation on paths in the Earth-to-space direction
����������������� 4.1.2���� Amplitude scintillation on paths in the space-to-Earth direction
������� 4.2���� Angle of arrival
������� 4.3���� Beam wander
������� 4.4���� Beam spreading
Annex 2� Detailed calculation of attenuation due to Rayleigh and Mie scattering
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