Research On RWA Optimization Algorithm Of Satellite Optical Network Based On Heuristic Algorithm

With the rapid development of the Internet and big data,users have demand for higher transmission rates and larger transmission capacity for satellite communication data transmission.Satellite microwave transmission technology is difficult to meet user needs.The use of satellite laser communication technology can greatly improve the quality and efficiency of communication information during transmission.Satellite optical networks have great development potential and will become the research hotspots and development trends of future satellite networks.It is expected to become the main form of future space communications.In satellite optical networks,routing and wavelength assignment(RWA)issues are critical factors that determine network performance.Using the ant colony algorithm to solve the RWA problem can not only optimize multiple targets,but also enable routing and wavelength assignment to be completed at the same time.The traditional ant colony algorithm has the advantages of high flexibility and low complexity,and can be used to solve the routing and wavelength assignment problems of satellite optical networks.However,the traditional ant colony algorithm has the disadvantages of easily falling into local optimum and slow convergence speed in the process of routing and wavelength allocation of satellite optical networks.At the same time,the uneven distribution of satellite services in location and time will lead to more congestion in hot spots.In order to solve the above problems,the satellite network routing and wavelength problems and the ant colony algorithm are researched in depth,and the RWA optimization algorithm based on the ant colony algorithm is researched to improve the algorithm path finding performance,improve the algorithm convergence speed,and add the algorithm congestion control mechanism.The main research contents and innovations of this article are as follows:(1)Extended pathfinding RWA algorithm based on heuristic algorithmWhen solving routing and wavelength assignment problems with traditional ant colony algorithms,due to pheromone update and routing rules,it's easy for the algorithm to fall into the local optimal.To overcome the effects,ant colony optimization based on an extended pathfinding routing and wavelength assignment algorithm(ACO-EP)is proposed.The algorithm considers the usage rate of wavelengths in the ant colony pathfinding process,optimizes the volatility coefficient,increases the random interference mechanism based on the service density,improves the ant colony algorithm's path optimization performance,and makes up for the ant colony algorithm's susceptibility to local optimization.The simulation studies the three performances of communication success rate,communication delay and blocking rate under different traffic densities.The results show that compared with the original Ant Colony Optimization Algorithm(ACO-original),the ACO-EP algorithm improves the communication success rate and reduces the communication delay and blocking rate.(2)Fast convergence RWA algorithm based on ant colony algorithmAiming at the problem that the initial pheromone of the traditional ant colony algorithm is evenly distributed and the satellite network topology information cannot be fully utilized,which leads to the slow convergence of the ant colony routing and wavelength assignment algorithm,a fast convergence ant colony routing and wavelength assignment algorithm(ACO-FC)is proposed.The algorithm makes full use of the relative relationship between the satellite network topology structure information and the source and destination nodes,that is,the direction guidance factor adjusts the routing probability,so that the initial ant colony performs routing based on the satellite optical network topology information instead of random selection to improve convergence speed.Combined with the particle swarm optimization algorithm,the pheromone is given a positive feedback to further improve the convergence speed of the algorithm.The simulation studies the algorithm convergence,the communication success rate and the communication delay performance under different service densities.The results show that compared with the original ant colony algorithm(ACO-original)and ant colony optimization algorithm with small window strategy algorithm(ACO-SWS),the ACO-FC algorithm improves the convergence speed and improves the communication success rate,and keep communication delay low.(3)Congestion control RWA algorithm based on traffic awarenessThe satellite communication user services are unevenly distributed in time and space,which results in large fluctuations in the traffic uploaded from the ground to the satellites.Without congestion control,local network congestion will occur and it will not be able to respond to services in real time.In view of the above problems,a traffic-aware Congestion Control Routing and Wavelength Assignment Algorithm(ACO-CCTA)is used.The algorithm obtains satellite network traffic through traffic awareness,calculates parameters such as average congestion,measures network load and average,and uses multipath transfer congestion for congested services that meet the conditions to reduce the satellite optical network blocking rate.Simulation studies performances of blocking rate,communication delay and wavelength resource usage under different service densities.The results show that compared with ACO-original and ACO-SWS,ACO-CCTA reduces the network blocking rate,maintains a low communication delay,and has a moderate wavelength resource utilization.