Uplinks Analysis and Optimization of Hybrid Vehicular Networks

2019 KSII Transactions on Internet and Information Systems  
5G vehicular communication is one of key enablers in next generation intelligent transportation system (ITS), that require ultra-reliable and low latency communication (URLLC). To meet this requirement, a new hybrid vehicular network structure which supports both centralized network structure and distributed structure is proposed in this paper. Based on the proposed network structure, a new vehicular network utility model considering the latency and reliability in vehicular networks is
more » ... etworks is developed based on Euclidean norm theory. Building on the Pareto improvement theory in economics, a vehicular network uplink optimization algorithm is proposed to optimize the uplink utility of vehicles on the roads. Simulation results show that the proposed scheme can significantly improve the uplink vehicular network utility in vehicular networks to meet the URLLC requirements. one of the most promising application scenarios in the fifth generation (5G) mobile communication systems [1] [2] . Different from the traditional mobile communication networks, the critical information generated by the vehicles need to be transmitted with very low latency and extremely high reliability [3] [4] . It is difficult for traditional vehicular networks to realize ultra-reliable and low latency communication (URLLC) [5] . How to design a dynamical vehicular network to achieve URLLC presents a great challenge. Currently, there are mainly two types of network structures used to realize vehicular networks in the existing studies, a centralized network structure based on cellular networks [6-8] and a distributed vehicular network structure, also known as the vehicular ad-hoc network (VANET) [9] [10] [11] . The advantage of LTE based centralized vehicular networks was discussed in [6] . In [7], a TD-LTE based vehicular network structure was introduced and the transmission reliability under different transmission distances was studied. The analysis results showed that LTE is a promising technology to support the long range vehicle to infrastructure (V2I) communications. However, the high latency remains as a key issue in LTE based vehicular networks. Since the low transmission reliability of messages in vehicular networks lead to the large resend time which does not guarantee the short handling time for security messages when there is a large distance between vehicle and road side unit. In fact, as one of the most important performance criteria in vehicular networks, the latency of transmitting critical information, such as the safety-related messages is one of key metrics to evaluate performance of a vehicular network [8] . In distributed VANET, vehicles on the road can communicate with each other via vehicle to vehicle (V2V) links and vehicle clusters are formed to provide a flexible network structure. In [9] , an access reliability model in VANET was proposed to analyze the vehicular access reliability with a fixed latency constraint. Connectivity probability under different traffic density for V2V communication scenarios in one-and two-way platoon-based VANETs was investigated in [10]. In [11], a one-dimensional multi-hop broadcasting model considering the different safe distances between vehicles was proposed to analyze the broadcasting success probability and multi-hop latency in VANETs. However, either centralized or distributed vehicular network structure cannot meet the URLLC requirements of future vehicular networks and can only satisfy parts of the vehicular network requirements [12] . To tackle this problem, in this paper, a hybrid vehicular network model which can adjust network structure dynamically is proposed to achieve URLLC, as a Pareto improvement strategy is deployed in the hybrid vehicular network which can lead to an optimal vehicular network utility under different distances between vehicles and the associated RSU. The contributions of this paper are summarized as follows. 1) To analyze the latency and reliability of messages in vehicular networks, a novel vehicular network utility model based on Euclidean norm theory is proposed for the hybrid vehicular networks. 2) By using the Pareto optimization, an uplink optimization algorithm is proposed to improve the vehicular network utility of uplinks in the hybrid vehicular networks. 3) Simulation results show that the proposed uplink optimization algorithm can significantly improve the uplink reliability and reduce the uplink latency. The vehicular network utility of the Pareto improvement strategy is improved up to 15%
doi:10.3837/tiis.2019.02.001 fatcat:mnrzdjl2arbedkwzq7kpasotae