Considering the scattering feature in the ultraviolet (UV) spectrum that can support communication for mobile unmanned aerial vehicles (UAVs), we deploy UAVs equipped with UV communication. Specifically, we focus on ground-to-air UV networks where the UAV collects data from the ground nodes. Assuming that the ground nodes are distributed in two dimensions, we analyze the air-ground connectivity probability. The influence of the transmitter divergence angle on the connectivity probability is investigated. Then, we analyze the probability that there exists interference from multiple nodes. To guarantee reliable communication under such interference, we further propose a handshaking-based UAV access protocol. By solving the coloring problem, we determine the time slot allocation for handshaking and propose a greedy channel allocation method to maximize the average system throughput. Numerical results show the performance gain of the proposed protocol over existing works.
{"title":"Connectivity analysis and user access design of ground-to-air ultraviolet communication networks","authors":"Lei Sun;Chen Gong;Zhengyuan Xu","doi":"10.1364/JOCN.527611","DOIUrl":"https://doi.org/10.1364/JOCN.527611","url":null,"abstract":"Considering the scattering feature in the ultraviolet (UV) spectrum that can support communication for mobile unmanned aerial vehicles (UAVs), we deploy UAVs equipped with UV communication. Specifically, we focus on ground-to-air UV networks where the UAV collects data from the ground nodes. Assuming that the ground nodes are distributed in two dimensions, we analyze the air-ground connectivity probability. The influence of the transmitter divergence angle on the connectivity probability is investigated. Then, we analyze the probability that there exists interference from multiple nodes. To guarantee reliable communication under such interference, we further propose a handshaking-based UAV access protocol. By solving the coloring problem, we determine the time slot allocation for handshaking and propose a greedy channel allocation method to maximize the average system throughput. Numerical results show the performance gain of the proposed protocol over existing works.","PeriodicalId":50103,"journal":{"name":"Journal of Optical Communications and Networking","volume":"16 10","pages":"1006-1017"},"PeriodicalIF":4.0,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142316347","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In datacenters, bursty and unevenly distributed traffic may lead to serious network performance degradation. Various methods, including reconfigurable optical circuit switching (OCS), traffic control techniques, valiant load balancing (VLB), and so on, have been proposed to solve this problem. Based on these solutions, our method makes a trade-off between cost and performance. In this paper, we propose to use multi-wavelength tunable transmitters in our previously proposed modular arrayed waveguide grating (AWG)-based interconnection network. We discuss how the multiple wavelengths can be shared in the network and then propose a computational model to study its blocking probability. Closed-form equations for low network load cases are also derived to provide the analytical expression for the blocking probability. We verify the accuracy of our computational model through simulations. Comparing the blocking probability of networks with and without multi-wavelength integrated transmitters, we show that network performance can be considerably improved after replacement. When traffic burstiness is 1.25 and traffic skewness is 0.08, the blocking probability is reduced from 0.14 to $3.60 times {10^{- 3}}$