Laserstråling gjennom turbulent atmosfære – Del 1 – stråling

The project "laser weapons and protection" within the research program "air defence, unmanned airborne systems and laser" has the goal to develop a high-power laser as a countermeasure against incoming projectiles, drones and similar. Since the laser effect is delivered on target through a typically turbulent atmosphere, it is relevant to estimate the atmosphere’s effect on the laser beam quality. This report (the first in a series) discusses the most used methods (the Rytov and Markov approximations) to calculate the general expectation values of the radiation field (which are the average field strength, the second-order correlation functions and, in case of the Rytov approximations, also the fourth-order correlation function) without specifying any particular atmospheric model.