Research On Internet Of Vehicles Multipath Collaborative Transmission Methods In Complex Mobile Scenarios

Internet of Vehicles(Io V)is an important application scenario for future mobile communications.Among the specific applications scenarios of the Io V,how to efficiently upload massive data generated by traditional network devices to the cloud server through the Io V is an important demand.This demand has a large number of application scenarios,such as highspeed railway communications and emergency communications.However,there are three challenges that need to be overcome for this demand.First,the limitations of single wireless link transmission.Second,the limitation of traditional network device on multipath transmission.Third,the impact of fluctuations of wireless link signals on multipath transmission.The Identifier Network is based on the new network architecture proposed by the National 973 Project and can support mobility very well.Therefore,in order to overcome the above three challenges and meet the demand of Io V applications,this dissertation,relying on the Identifier Network,considering the characteristics of complex mobile scenarios,and solving the following three research questions: 1)How to design a multipath transmission framework that supports the integration of different hardwares and protocols? 2)How to improve the fault tolerance of the transmission framework mentioned in this dissertation? 3)Based on the question 2,how to design a multipath transmission scheme that comprehensively considering the characteristics of complex mobile scenarios to improve the transmission performance of Io V? The main contributions of the dissertation are:(1)For the first question,on the basis of comprehensive analysis of wireless link status in different scenarios,this dissertation proposes the demands of a new type of Io V multipath transmission framework.And based on the Identifier Network,this dissertation designs an Identifier Io V multipath collaborative transmission framework.The transmission framework integrates the heterogeneous wireless links around the vehicle.It establishes a transparent transmission tunnel,and realizes the "separation of users and network" and "separation of resources and location".It also abstracts the resource management model as "three layers and two mappings" in the core device,thus completing the flexible control and distribution of the transmission strategy,and realizing the "separation of control and forwarding".(2)For the second question,this dissertation proposes a multipath transmission method which can tolerate the links’ state estimation errors.Considering the links’ statue estimation error in mobile scenarios,this method deploys a buffer at the receiving end to dynamically increase the queuing delay of out-of-order packets,avoiding the sending end from reducing the transmission rate due to out-of-order transmission,and indirectly improving the resource utilization of transmission framework.This method is compared with the classic method in terms of out-of-order fault tolerance,real-time throughput,delay,and tolerance of estimated error.The test results show that this method effectively tolerates links’ statue estimation error,overcomes the out-of-order packets,and improves the transmission performance.(3)For the second question,this dissertation proposes a multipath transmission fault tolerance method based on Bignum network coding from the perspective of wireless link transmission packet loss.Considering the problem of excessive resource overhead of the traditional method,this method ensures the reliability of transmission based on a brand new network coding model.In this dissertation,through numerical analysis,simulation comparison,and system test,the transmission loss tolerance of the method,codec time,real-time throughput and universality are analyzed.The test results show that this method significantly improves the transmission reliability of heterogeneous wireless links and indirectly improves the resource utilization rate of heterogeneous wireless links.In addition,in the simulation experiment,in order to complete the test that can not be completed in the real system,this dissertation designs the Identifier Io V multipath collaborative transmission simulation system.With this simulation system,it is possible to fully compare the performance differences of different transmission methods in the Identifier Io V multipath collaborative transmission framework from various aspects.(4)For the third question,based on the last two contributions,considering the problem of loss packets and out-of-order packets,firstly,this dissertation proposes an outof-order fault tolerant receive buffer for multipath transmission that adapts to network coding model.The buffer takes the coding cluster as the sorting target,which ensures the in-order transmission of the multipath transmission method that supports network coding.Secondly,based on the buffer,this dissertation designs the Identifier Io V multipath collaborative transmission scheme.Finally,through simulation and real tests,it is verified that in complex mobile scenarios,this scheme can comprehensively improve the resource utilization and transmission performance of the Io V compared with classic multipath transmission schemes.At present,this scheme has been deployed in the real system of the government and enterprises,creating good social and economic benefits.Through the above research on the Io V multipath transmission framework and related scheme based on the Identifier Network,this dissertation provides a feasible new solution for the Io V multipath transmission.