Research On Ship Data Scheduling Algorithm Based On Maritime Communication Network

At present,the maritime communication system mainly includes the maritime wireless communication system,the maritime satellite communication system and the shore-based mobile communication system,which basically realizes the full coverage of the maritime communication network.The system guarantees routine communication between coastal,offshore and ocean-going ships and coasts,ships and ships.In marine,oil and gas exploration and development,marine environmental monitoring,marine fisheries,mariculture,marine science and other fields can provide accurate,timely and safe communication equipment.However,maritime communication technology is still in a low application stage,which can only meet the basic communication needs of traditional maritime activities.Although users can also choose different communication systems according to the sea area of maritime activities and the type of business they are engaged in,the advantages and disadvantages of each system are obvious.And it is far from being able to achieve remote network coverage.At the same time,the marine communication network and the traditional communication network are incompatible with each other,the communication bandwidth is different,there are blind spots in the coverage area,lack of flexible configuration and efficient unified management mechanism.Therefore,the traditional maritime communication network is more and more difficult to meet the increasing demand for marine activities in China,and has become a major bottleneck restricting the development of marine development and exploration.The International Maritime Organization(IMO)has also put forward the strategy of developing electronic navigation to meet the needs of future business expansion,user needs and marine environmental protection in the field of navigation.Therefore,how to use the existing communication equipment to reasonably allocate and establish the maritime broadband communication system is an urgent problem to be solved.In this paper,we first apply the concept of software-defined network to the existing maritime communication system.It is a new network mode,which separates the hardware part of the execution and forwarding from the control decision-making part.This provides a possibility for the overall optimization of ship data scheduling.Secondly,the concept of delay tolerance network is combined into the specific problem of ship cooperative transmission,and the situation of delay tolerance network considering the interruption of communication is very consistent with the characteristics of maritime communication.Under these two conditions,we study the scheduling problem of the ship uploading information to the base station through the maritime communication system.For this scenario,the problem is divided into two parts to solve the problem.Since the ship can only upload data within a fixed length of time,the first part considers uploading as many significant packets as possible under a given transmission time,and screening all data packets that have been generated.The data scheduling is optimized by the method of decision graph.In the second part,we consider further improving the communication performance on the basis of task selection,and propose the concept of minimizing delay multiplying by weight.Finally,combined with the characteristics of delay tolerance network,multi-vessel cooperative transmission is realized.In this paper,the idea of time-capacity mapping is used to transform intermittent resource scheduling into a continuous scheduling problem.We also propose a dynamic programming algorithm based on neighborhood search to reduce the time complexity of the algorithm by reducing the number of solutions in the solution space.The performance of the algorithm is verified by MATLAB.