Networking And Implementation Of Hybrid Communication Network

In recent years,with the development of the national smart grid,the tunneling of power grids and the networking of cable tunnels are gradually forming.The routing inspection of cable tunnel is needed to ensure that the operation of cable tunnel is efficient and safe.At present,the inspection is mainly on a regular basis by manual method.Due to the special environment of cable tunnels,the safety issues of workers in tunnels are of great concern.The inspection activities under the smart grid not only have the needs of communication intelligence,but also have needs for locating fault quickly and accurately,guaranteeing the safety of the inspectors,and solving the problem of failure of wireless communication servive in cable tunnels.Based on the above requirements,the combination of Visible Light Communication(VLC)technology and Power Line Communication(PLC)technology is applied in cable tunnel to form the hybrid network communication system.The system provides a safe and convenient wireless location information service for inspectors.It realized the ‘last mile' communication of the smart grid and provides a new solution for communication in the cable tunnel.The main research content of this paper is as follows:First,designed and implemented the master station software system for the hybrid communication network system.The master station software system integrates the information management system with the instant messaging system.The system is divided into information management service module,communication module and positioning display module.The information management service module is in charge of the personnel information,tunnel information,substation information and LED lamp information.The communication module is responsible for providing instant messaging service for text,voice,and image for users and inspecting site personnel.The positioning display module shows the location information of patrol personnel and the access state of access point for users' visual function.The system uses the Client/Server structure,and uses the database My SQL to storage data.In this system,the socket network communication technology based on TCP is used to communicate with the inspectors in the cable tunnel.Moreover,the design and debugging of the main station software system that based on the Microsoft Visual Studio platform have been completed.The coding and debugging work of the master station software system has been completed.Software test have proved that the master station software system is in good operating condition and meets the needs of the user project.Second,in order to further improve the transmission rate of the hybrid network communication system,an optimization algorithm of transmission power allocation based on relay power optimization is proposed to solve the maximum achievable rate problem.For the characteristics of the downlink of the hybrid network communication system,the transmission power allocation model with the highest achievable rate is established.This model optimizes the allocation of transmission power.It transmits the signal through PLC-VLC cascaded system and Wi-Fi system to achieve the goal of improving the system's achievable rate.The simulation results show that the algorithm can dynamically allocate the transmit power according to different channel states and can effectively improve the system achievable rate.