This PDF file contains the front matter associated with SPIE Proceedings Volume 12068, including the Title Page, Copyright information, and Table of Contents

In this paper, the performance of a multihop free-space optical system is studied. The system adopts all-optical amplify-and-forward relays and heterodyne differential phase-shift keying (DPSK) technique, considering Gamma-Gamma turbulence fading with pointing error. The novel closed-form expressions for the probability density function (PDF) and the cumulative distribution function (CDF) of the end-to-end signal-to-noise ratio (SNR) are derived. Based on these statistics, closed-form expressions for the outage probability, the average bit-error rate (BER), and the ergodic capacity of the all-optical relaying multihop system are presented. The analytical results are obtained.

We propose a potentially practical scheme to entangle two distant atomic Bose-Einstein condensates (BEC), which is respectively in an optical cavity. Due to interaction between the cavity and the atomic BEC and the cavity decay, a linear polarized single-photon, which inputs the cavity, will rotate a certain angle after the input-output process, which is called Faraday rotation. Thanks to the faraday rotation of the photonic polarization, through detecting the output photonic polarization, we will entangle two distant Bose-Einstein condensates and generate entangled coherent states. Therefore, we provide a possible way to realize long-distance macroscopic quantum entanglement.

Compared with fiber optical current sensors, integrated optical current sensors (IOCS) replace optical fiber with integrated optical waveguide materials, which is suitable for further miniaturization, modularization and low cost of sensors and has become a research hotspot in recent years. In this study, the research progress of IOCS in the world is reported. The IOCS which are realized by the ways of faraday magnet-optic effect and thermal-optic effect are shown respectively. Simultaneously, the performance of IOCS based on different sensing units are compared and their advantages and disadvantages are analyzed. Finally, the current challenge and future development trends of IOCS are summarized.

Cat’s eye lens make the laser beam retro-reflected exactly to the opposite direction of the incidence beam, called cat’s eye effect, which makes rapid acquiring, tracking and pointing of free space optical communication possible. Study the influence of cat’s eye effect to cat’s eye retro-reflector at large incidence angle is useful. This paper analyzed the process of how the incidence angle and focal shit affect effective receiving area, retro-reflected beam divergence angle, central deviation of cat’s eye retro-reflector at large incidence angle and cat’s eye effect factor using geometrical optics method, and presented the analytic expressions. Finally, numerical simulation was done to prove the correction of the study. The result shows that the efficiency receiving area of cat’s eye retro-reflector is mainly affected by incidence angle when the focal shift is positive, and it decreases rapidly when the incidence angle increases; the retro-reflected beam divergence and central deviation is mainly affected by focal shift, and within the effective receiving area, the central deviation is smaller than beam divergence in most time, which means the incidence beam can be received and retro-reflected to the other terminal in most time. The cat’s eye effect factor gain is affected by both incidence angle and focal shift.

The pointing error (pointing deviation) of light beam is an important factor affecting the signal transmission quality of underwater optical communication system. Here we investigated the effects of weak turbulent seawater on the propagation of orbital angular momentum(OAM) modes carried by deflection Bessel Gaussian beams. The analytic expression of the received probability of the signal and crosstalk OAM mode was derived based on the theories of Rytov theory. The results show that smaller deflection has a significant effect on the improvement of signal received probability. And with the increase of the dissipation rate of the mean-squared temperature and the decrease of the rate of dissipation of kinetic energy per unit mass of fluid, the turbulence of seawater increases, and the influence of turbulence on the beam increases Our results also indicate that the received signal probability can be improved by use of deflection Bessel Gaussian beams with low OAM quantum number and long wavelength.

We discussed the influence of weak turbulent seawater on the capacity of underwater optical communication channel. A channel capacity model of shifted and deflected Bessel Gaussian beam links is derived. The results show that the channel capacity decreases as the rate of dissipation of kinetic energy per unit mass of fluid and the inner scale decrease, and it increases as the increase of the dissipation rate of the mean-squared temperature as well as the outer scale. And the channel capacity increases with the increase of the number of channels and the decrease of the angular half-aperture of the cone and shift.

Aiming at the problem of fiber break failure of optical fiber connector used in aerospace wide temperature range environment, the finite element simulation model is established based on the mature optical fiber contact structure. The influence of some typical factors, such as expansion coefficient of fiber adhesive, filling amount of adhesive, and material of metal tailstock, on the internal stress of optical fiber contact parts is analyzed quantitatively at extreme temperature of +100℃ and -100℃. It is found that the axial force exerted on the fiber by the metal tailstock and ceramic ferrule due to high and low temperature expansion and contraction is the main source of the internal stress. The junction area of ceramic ferrule cone and straight section is the most prone to fiber breakage. The difference between the maximum axial internal stress of optical fiber at +100℃ and -100℃ is regarded as the index to evaluate the internal stress of optical fiber. The metal tailstock with low expansion coefficient can significantly reduce the internal stress of optical fiber. Compared with aluminum alloy tailstock, the maximum stress difference of Kovar alloy tailstock can be reduced by 51.5%. The internal stress of optical fiber can be reduced to a certain extent by appropriately reducing the filling amount of optical fiber adhesive between ceramic core and metal tailstock and the expansion coefficient of optical fiber adhesive. The results show that the maximum stress difference can be reduced by 11.4% if only the conical region is filled. When the thermal expansion coefficient of optical fiber adhesive decreases from 60e-6/℃ to 30e-6/℃, the maximum stress difference declines by 8.9%. This paper can provide a reference for improving the design of optical fiber connector for aerospace wide temperature range.

With the arrival of the 5G mobile communication technology, Internet traffic is expected to grow threefold globally in the next five years. In order to meet the demand of explosive service and the construction of intelligent Optical Network in the future, a backbone transmission Network based on Wavelength Switched Optical Network (WSON) arises at the historic moment. But the WSON backbone transmission network also faces the limitation of network capacity. This paper proposes a link scoring algorithm, scores each link and chooses the link which gets the highest score to expand, which can quantitatively evaluate the link status and find the network capacity bottleneck. Using the algorithm, it uses 12 iterations to transmit the traffic, while uses 16 iterations choosing the traditional method. By choosing to expand the bottleneck link step by step, the transmission cost can be minimized.

Combining SDN and NFV technology, network slicing technology can share the physical network by dividing it into multiple isolated virtual logical networks, which become an important solution for 5G mobile bearer network to carry heterogeneous services. We design and implement a network slice management system in this paper. The system can not only quickly deploy multi-level isolated network slices (RRU-DU-CU-MEC) to meet the needs of tenants, but also realize the adaptive adjustment of resources through the monitoring of network resources and processing resources.

With the development of edge computing, the edge data center of optical interconnection has attracted extensive attention due to its storage, computing, and large bandwidth capabilities. Caching popular content in the edge data center has been proposed to reduce network load and latency. Due to the limited capability of a single edge data center, multiple edge data centers are required to cooperate to meet specific business requirements. Data in the edge computing optical network is distributed according to area deployment. Coordination between data centers will cause resource waste and delay due to the asynchronous transmission time. We designed and implemented a latency-controlled distributed content caching and data aggregation experiment in the MEC-empowered metro optical networks. The system can not only realize dynamic network configuration and service deployment but also reduce the average delay and improve the resources utilization.