A Survey on Obstacle Modeling Patterns in Radio Propagation Models for Vehicular Ad Hoc Networks

Abstract

Vehicular ad hoc networks (VANETs) form an evolving field of wireless technology that focuses on a wide range of useful applications from safety-related applications to infotainment services. Radio propagation models (RPMs) in VANETs require a high level of realistic detail due to mobility, the nature of the network, technology limitations and urgency of information dissemination. Hence, developing realistic RPMs in VANETs is a challenging task. Nonetheless, a number of traditional models are considered realistic; however, the absence of a required level of detail is a critical aspect of currently employed RPMs. For instance, modeling obstacles in VANETs is a challenging research perspective. Two types of radio obstacles exist in an urban transportation environment: moving obstacles and static obstacles, both of which block radio signals in vehicle-to-infrastructure and vehicle-to-vehicle communication. In this paper, a thematic taxonomy of existing RPMs is proposed and the major challenges involved in modeling realistic radio propagation for VANETs, especially in urban environments, are presented. Existing RPMs are classified and compared using the proposed taxonomy. These RPMs are grouped according to obstacle modeling pattern and are analyzed using important parameters, such as received signal strength, packet delivery ratio, delivery latency and average path length. Issues and challenges with existing RPMs are put forward and recommendations that may be helpful for developing realistic RPMs are made.