Resource Competition And Cooperation Mechanism In Intelligent Transportation Networks

In recent years, with the rapid development of wireless communication technology and modern automobile industry, intelligent transportation networks came into being. By establishing communication among vehicles,pedestrians and roadside communication infrastructures, the intelligent transportation networks can provide services such as nearby vehicle perception, danger warning, vehicle-road cooperative control and message transmission. The intelligent transportation networks, which aims to protect traffic safety, improve traffic efficiency and driving experience, has attracted worldwide attention from academia and industry.The efficient and rational utilization of communication resources is an important research direction of intelligent transportation networks.However, since the intelligent transportation networks is characteristic by the scarcity of communication resources, the rapid movement of vehicle nodes, the short communication range between vehicles and the quickly changing network structure, when the network nodes use limited communication resource to transmit information, sometimes they need to compete with each other, and sometimes they need cooperation. In this paper, we study the efficient utilization of communication resources on different scenarios including collaborative content distribution among vehicles, UAV-assisted post-disaster vehicle communication and resource sharing among Long Term Evolution-Vehicle (LTE-V) and other communication technologies. The main contributions of this paper are summarized as follows.1. Content Distribution among Vehicles Based on Coalitional Game TheoryThe inter-vehicle collaborative content distribution service aims at improving the comfort of the traveler's journey. This service distribute messages to vehicles in the specific road area. In the inter-vehicle collaborative content distribution service, vehicles can adopt cooperation and competition mechanism. The cooperation mechanism means that the messages can be shared among vehicles through inter-vehicle communication, and the competition mechanism means that vehicles compete with each other to transmit messages for the purpose of getting rewards from message providers. In this paper, we study the message sharing among vehicles and analyze how to stimulate vehicles to cooperate.A coalitional game theory-based collaborative content distribution scheme is proposed. Finally, we built simulation platform based on NS3 and SUMO. Simulation results indicate that the proposed scheme significantly speed up the message sharing among vehicles and improve the efficiency of the inter-vehicle collaborative content distribution service.2. Analyzing and Improving the Connectivity among Vehicles on The UAV-aided Post-Disaster Inter-Vehicle Communication ScenarioAfter disasters, roadside communication infrastructures, which can provide wireless communications to vehicles, may fail due to physical damages or power outages. At this time, unmanned aerial vehicle (UAV)nodes can be added to improve the connectivity among vehicles through the cooperation of inter vehicle communication links and vehicle-to-UAV communication links. In this paper, the deployment UAVs to improve connectivity among vehicles in disaster affected areas is analyzed. We model the channels between vehicles and UAVs in suburban, urban and dense urban areas, and analyze the impact of the UAV altitude on the probability of Line-of-sight communication, path loss and shadow fading loss. The relationship between the altitude of the UAV and the connectivity among vehicles is obtained and we prove that there are optimal UAV altitudes for different scenarios. Finally, simulation results verify that there exist optimal UAV altitudes for different scenarios.3. Research on Resource Sharing between LTE-V and DSRCLTE-V and Dedicated Short Range Communication (DSRC) are communication technologies in the intelligent transportation networks, and they may operate in the same spectrum. To achieve that LTE-V devices and DSRC devices operating on the same spectrum, firstly, we propose a resource allocation scheme to avoid inter-system interference. Secondly, in order to enhance the cooperation between the LTE-V system and the DSRC system, we improve the LTE-V device receivers so that LTE-V devices can receive both the LTE-V signal and the DSRC signal. Finally, the signal reception is verified by link-level simulation. The results show that the improved LTE-V device can effectively receive the signal transmitted by the DSRC device.4. Research on Resource sharing among LTE-V users and LTE non-vehicle usersLTE-V users and LTE non-vehicle users need to compete to use the communication resources of the cellular networks when transmitting messages. In this paper, firstly, we analyze the impact of one of LTE-V users' communication services, i.e. the vehicle driving status information collection service, on LTE non-vehicle users' communication services.Secondly, a vehicle driving status information collection scheme combining LTE vehicle-to-vehicle (V2V) communication and LTE vehicle-to-infrastructure (V2I) communication is proposed. In the scheme,roads are divided into many areas. In each area, one car is selected as gateway, which receives the driving status information of surrounding vehicles through LTE V2V communication and uploads those information to LTE base station through LTE V2I communication. Finally,numerical analysis based on Markov model is used to verify the scheme. The results show that the scheme can effectively reduce the occupancy of LTE cellular network communication resources by the vehicle driving status information collection service of LTE-V users, thus can reduce the impact of LTE-V users' services on LTE non-vehicle user services.