Numerical Investigation into Focal Shift of Gaussian Beam Propagating in Turbulent Atmosphere
湍流大气中高斯光束焦移的数值模拟研究

The focal shift of a focused Gaussian beam propagating in turbulent atmosphere is investigated using numerical simulation. It is found that the focus always shifts toward the transmitter, and the length of the focal shift will increase with the increasing of turbulence strength.These results are in excellent agreement with theoretical results. By using focal depth the collimated characteristic of beam near focus is described. Simulation results show that focal depth increases with turbulence strength for weak to moderate turbulence, and in cases of moderate to strong turbulence the beam is highly collimated on both sides of the beam waist.