Analysis of Access and Connectivity Probabilities in Vehicular Relay Networks

IEEE 802.11p and 1609 standards are currently under development to support Vehicle-to-Vehicle and Vehicle-to-Infrastructure communications in vehicular networks. For infrastructure-based vehicular relay networks, access probability is an important measure which indicates how well an arbitrary vehicle can access the infrastructure, i.e. a base station (BS). On the other hand, connectivity probability, i.e. the probability that all the vehicles are connected to the infrastructure, indicates the service coverage performance of a vehicular relay network. In this paper, we develop an analytical model with a generic radio channel model to fully characterize the access probability and connectivity probability performance in a vehicular relay network considering both one-hop (direct access) and two-hop (via a relay) communications between a vehicle and the infrastructure. Specifically, we derive close-form equations for calculating these two probabilities. Our analytical results, validated by simulations, reveal the tradeoffs between key system parameters, such as inter-BS distance, vehicle density, transmission ranges of a BS and a vehicle, and their collective impact on access probability and connectivity probability under different communication channel models. These results and new knowledge about vehicular relay networks will enable network designers and operators to effectively improve network planning, deployment and resource management.

IEEE 802.11p和1609标准目前正在开发中，以支持车载网络中的车对车和车对基础设施通信。对于基于基础设施的车载中继网络，接入概率是一项重要指标，它表明任意车辆接入基础设施（即基站）的能力。另一方面，连通概率，即所有车辆都连接到基础设施的概率，表明了车载中继网络的服务覆盖性能。在本文中，我们开发了一个具有通用无线信道模型的分析模型，以全面描述车载中继网络中考虑车辆与基础设施之间的单跳（直接接入）和两跳（通过中继）通信时的接入概率和连通概率性能。具体而言，我们推导出了用于计算这两个概率的闭式方程。我们的分析结果通过仿真得到验证，揭示了关键系统参数之间的权衡，例如基站间距离、车辆密度、基站和车辆的传输范围，以及它们在不同通信信道模型下对接入概率和连通概率的综合影响。这些关于车载中继网络的结果和新知识将使网络设计者和运营商能够有效地改进网络规划、部署和资源管理。