Considerations for application of Laguerre-Gaussian beam wave in optical wireless communication

摘要

Effect of scintillations is a serious problem in optical systems which require atmospheric propagation, and various examinations have been implemented to keep communication quality. But combination of optical conditions to optimize communication capability has not been examined. In this paper, optimization of the combination of optical variables, for example transmission beam radius of carrier wave and diameter of receiving aperture, is conducted by using the log-normal distribution model in weak turbulence and the gamma-gamma distribution model, which is suitable for weak to strong turbulence, in moderate to strong turbulence with considering aperture averaging. As a result of the examination, the optimum combination have been successfully found. Moreover, to investigate the propagation mode of carrier wave, comparison of propagation attenuation between Gaussian beam wave and Laguerre-Gaussian beam wave and evaluation of communication quality in optimized optical condition obtained from above-mentioned examination, will be done. The result is that the propagation loss of any of the Laguerre-Gaussian beam waves are smaller than those of the Gaussian beam waves. It is also observed that the propagation loss of (5, 1) Laguerre-Gaussian beam wave is particularly small among those.