Research On Optimization Algorithm Of Hybrid FSO/RF Communication System

Wireless communication has evolved from a simple voice communication into voice, data, images, video and other means of communication. The demand for bandwidth became bigger and bigger. The scarce Radio Frequency(RF) spectrum and inter-channel interference become fundamental limits to network performance, and increasing RF links lead to added interference which may seriously degrade the quality of communication. Moreover, free space optical communication(FSO) is significantly influenced by environmental factors, when used alone reliability is low. Hybrid FSO/RF system provides a new way to solve this problem.This article study the impact of adverse environmental factors on the FSO link and RF link, and mainly analysis the attenuation of rain and fog. Then in order to ensure the communication quality and transmission rate, we need to optimize the design of hybrid FSO/RF communication links. We proposed hybrid FSO/RF optimization algorithm based on power adaptive, so that the system can save energy and receive good environmental robustness simultaneously.Several frameworks have been proposed for such hybrid networks. In their model, each node is equipped with both RF and FSO transceiver, the objective is to provide backup routes for each other. This assumption guarantee the reliability of the system but may be impractical due to the high cost of FSO links. Most current wireless networks is based on RF technology, We need to use MILP algorithm to augment RF WMNs with FSO link, so that the network can achieve the larger network throughput and optimal performance when the number of FSO links is minimum(the cost is lowest). It establishes a structure model of random node network and obtains the throughput optimization scheme for hybrid RF/FSO network by using a mixed integer linear programming(MILP) algorithms, allocating these FSO links and choosing routing, scheduling schemes properly to achieve this throughput, which has a significant influence for the performance improvement of hybrid RF/FSO network.