This article takes the “first step” attitude to seize the development opportunities of 5G and its group technology, make full use of the functions of 5G mobile Internet, and promote the application of 5G communication technology in the field of the library. On the basis of designing a three-dimensional real-time book tracking map, etc., the author put forward the concept of a future smart library based on 5G mobile Internet.

The propagation behaviours of a sin-Gaussian beam (SiGB) with astigmatism in oceanic water is analysed. The analytical expressions for the average intensity of such a beam are derived by using the extended Huygens-Fresnel integral. Its average intensity and on-axial intensity distributions in oceanic water are numerically examined. Then, we mainly focus on the effect of the beam parameters and the medium structure constant on the propagation behaviours for the astigmatic SiGBs in oceanic water, revealing that the evolutions of the intensity distributions can be effectively modulated by adjusting the astigmatic parameter, coherence length and the atmosphere turbulence strength.