Research On Transmission Bandwidth Optimization Of Satellite Navigation System

Satellite navigation system has been widely used in many fields such as industry,national defense,medical treatment and communication.With the increasing demand of users and service types,the data types transmitted by satellite navigation system become more and more abundant,and the bandwidth allocation problem becomes more and more serious.Therefore,this paper makes an in-depth study on the transmission bandwidth optimization technology of satellite navigation system.The main research work is summarized as follows:On the basis of studying and analyzing the service data types and data link layer transmission protocols of satellite navigation system,in this paper,two key technologies for optimal transmission bandwidth of satellite navigation system are proposed,i.e.,as a bandwidth optimization technique and a channel bandwidth optimization technique.For the problems of low packet multiplexing efficiency,large buffer overflow probability and low bandwidth utilization rate caused by the fixed frame generation time in the traditional frame generation algorithm,the concept of frame generating time threshold(FGTDT)is proposed,and the frame bandwidth optimization algorithm of FGTDT based on finite cache is designed.The core idea of the algorithm is that if a frame can be generated within the range of FGTDT,the frame can be generated without waiting for the cut-off time,otherwise the frame can be generated only after the cut-off time.The simulation results show that the buffer overflow probability can be reduced and the frame transmission bandwidth can be optimized by controlling the start time and the cut-off time of frame generation.Aiming at the problem that the traditional channel scheduling algorithm uses only one scheduling algorithm for real-time traffic and non-real-time traffic,which will lead to large transmission delay and serious channel competition,this paper designs a mixed scheduling channel bandwidth optimization algorithm,a maximum real-time urgency priority algorithm is designed for real-time traffic to ensure the timeliness of real-time traffic,and a first-come first-served Algorithm is adopted for non-real-time traffic to ensure the fairness of non-real-time traffic.The simulation results show that the hybrid scheduling channel bandwidth optimization algorithm can effectively reduce the system buffer pressure,reduce the channel delay,optimize the channel bandwidth of satellite navigation system.