Aperture-averaged scintillation index and fade statistics in weak oceanic turbulence

• 作者: Hao Wang Fu-Zeng Kang Xuan Wang Wei Zhao Shu-Wei Sun
• 来源期刊: 中国物理B（英文版）
• 年，卷（期）: 2021,（6）
• 所属期刊栏目: ELECTROMAGNETISM, OPTICS, ACOUSTICS, HEAT TRANSFER, CLASSICAL MECHANICS, AND FLUID DYNAMICS
• 页码范围: 363-372
• 页数: 10页
• 语种: 英文
• DOI: 10.1088/1674-1056/abd756

摘要

With the rapid demand for underwater optical communication (UOC),studies of UOC degradation by oceanic tur-bulence have attached increasing attention worldwide and become a research hot-spot in recent years.Previous studies used a simplified and inaccurate oceanic turbulence spectrum,in which the eddy diffusivity ratio between temperature and salinity is assumed to be unity and the outer scale of turbulence is assumed to be infinite.However,both assumptions are not true in most of the actual marine environments.In this paper,based on the Rytov theory in weak turbulence,we derive analytical expressions of "the aperture-averaged scintillation index" (SI) for both plane and spherical waves,which can clearly demonstrate how SI is influenced by several key factors in UOC.Then,typical fade statistics of the UOC system in weak turbulence is discussed including the probability of fade,the expected number of fades per time,the mean fade time,signal-to-noise ratio and bit error rate.Our results show that spherical wave is preferable in the UOC system in weak tur-bulence compared to plane wave,and the aperture-averaged effect has a significant impact on UOC system's performance.Our results can be used to determine those key parameters for designing the UOC system over reasonable ranges.