A comprehensive survey on vehicular Ad Hoc network

Vehicle-to-anything (V2X) communications refer to information exchange between a vehicle and various elements of the intelligent transportation system (ITS), including other vehicles, pedestrians, Internet gateways, and transport infrastructure (such as traffic lights and signs). The technology has a great potential of enabling a variety of novel applications for road safety, passenger infotainment, car manufacturer services, and vehicle traffic optimization. Today, V2X communications is based on one of two main technologies: dedicated short-range communications (DSRC) and cellular networks. However, in the near future, it is not expected that a single technology can support such a variety of expected V2X applications for a large number of vehicles. Hence, interworking between DSRC and cellular network technologies for efficient V2X communications is proposed. This paper surveys potential DSRC and cellular interworking solutions for efficient V2X communications. First, we highlight the limitations of each technology in supporting V2X applications. Then, we review potential DSRC-cellular hybrid architectures, together with the main interworking challenges resulting from vehicle mobility, such as vertical handover and network selection issues. In addition, we provide an overview of the global DSRC standards, the existing V2X research and development platforms, and the V2X products already adopted and deployed in vehicles by car manufactures, as an attempt to align academic research with automotive industrial activities. Finally, we suggest some open research issues for future V2X communications based on the interworking of DSRC and cellular network technologies.

Interworking of DSRC and Cellular Network Technologies for V2X Communications: A Survey

Inter-vehicle communication (IVC) systems (i.e., systems not relying on roadside infrastructure) have the potential to radically improve the safety, efficiency, and comfort of everyday road travel. Their main advantage is that they bypass the need for expensive infrastructure; their major drawback is the comparatively complex networking protocols and the need for significant penetration before their applications can become effective. In this article we present several major classes of applications and the types of services they require from an underlying network. We then proceed to analyze existing networking protocols in a bottom-up fashion, from the physical to the transport layers, as well as security aspects related to IVC systems. We conclude the article by presenting several projects related to IVC as well as a review of common performance evaluation techniques for IVC systems.

/pdf/inter-vehicle-communication-systems-a-survey-4dcec4ylxn.pdf

Inter-vehicle communication systems: a survey

Vehicular Ad-Hoc Networks (VANETs) enable communication among vehicles as well as between vehicles and roadside infrastructures. Currently available software tools for VANET research still lack the ability to asses the usability of vehicular applications. In this article, we present Traffic Control Interface (TraCI) a technique for interlinking road traffic and network simulators. It permits us to control the behavior of vehicles during simulation runtime, and consequently to better understand the influence of VANET applications on traffic patterns.In contrast to the existing approaches, i.e., generating mobility traces that are fed to a network simulator as static input files, the online coupling allows the adaptation of drivers' behavior during simulation runtime. This technique is not limited to a special traffic simulator or to a special network simulator. We introduce a general framework for controlling the mobility which is adaptable towards other research areas.We describe the basic concept, design decisions and the message format of this open-source architecture. Additionally, we provide implementations for non-commercial traffic and network simulators namely SUMO and ns2, respectively. This coupling enables for the first time systematic evaluations of VANET applications in realistic settings.

TraCI: an interface for coupling road traffic and network simulators

The need of a medium access control (MAC) protocol for an efficient broadcast service is of great importance to support the high-priority safety applications in vehicular ad hoc networks (VANETs). This paper introduces VeMAC, a novel multichannel TDMA MAC protocol proposed specifically for a VANET scenario. The VeMAC supports efficient one-hop and multihop broadcast services on the control channel by using implicit acknowledgments and eliminating the hidden terminal problem. The protocol reduces transmission collisions due to node mobility on the control channel by assigning disjoint sets of time slots to vehicles moving in opposite directions and to road side units. Analysis and simulation results in highway and city scenarios are presented to evaluate the performance of VeMAC and compare it with ADHOC MAC, an existing TDMA MAC protocol for VANETs. It is shown that, due to its ability to decrease the rate of transmission collisions, the VeMAC protocol can provide significantly higher throughput on the control channel than ADHOC MAC.

/pdf/vemac-a-tdma-based-mac-protocol-for-reliable-broadcast-in-3borkj99g2.pdf

VeMAC: A TDMA-Based MAC Protocol for Reliable Broadcast in VANETs

This document summarizes and describes the main building blocks of the Car2X Communication System as it is pursued by the Car2Car Communication Consortium (C2C-CC). “Car2X” means interactions among cars, between cars and infrastructures, and viceversa. It provides interested readers with an introduction to Car2X communications. It is intended to be a living document which will be complemented according to the progress of the work of the C2C-CC. One main objective of this document is to give insight into ongoing and upcoming activities, such as public funded projects which target to contribute to the C2C-CC specifications, an overview on ongoing work and results achieved so far. In addition, this document provides concepts and technologies that have been developed or identified by the C2C-CC and assessed as necessary building blocks to be proposed for a standard.

Car-2-Car Communication Consortium - Manifesto

Vehicular Ad Hoc Networks (VANETs) represent an emerging topic in wireless communication and networking VANETs are currently receiving a lot of attention due to their promise of considerably increasing safety and comfort while being on the road High mobility, adverse channel conditions, and market introduction are some of the key challenges one has to deal with when designing these spontaneous networks Inter-Vehicle-Communications Based on Ad Hoc Networking Principles covers results and achievements of the FleetNet project, a project devoted to the design of a vehicular ad hoc network

Inter-Vehicle-Communications - Based on Ad Hoc Networking Principles : The FleetNet Project

Within the framework of the FLEETNET project, a real-world ad hoc network testbed was built using cars as mobile nodes. These cars were equipped with computing and communication devices. As ad hoc routing algorithm, position-based forwarding implemented on Linux-based laptops was used, exploiting position information gathered by on-board navigation systems. We report on measurements and experiences with this testbed for static 1-hop and 3-hop scenarios as well as for mobile 3-hop scenarios. Beside the power, loss-rate, throughput and delivery ratio measurements, we present our methodology for conducting experiments with 'real-world' mobile ad hoc networks and discuss problems of beacon-based position-based routing due to radio fluctuations.

Performance measurements of a vehicular ad hoc network

Driving means constantly changing location. This, in turn, means a constant demand for information on the current location and specifically for data on the surrounding traffic. In particular, there is a demand for sensor data from other cars such as data on braking sent from a preceding car, for data on the traffic flow on a route, and for information about sites located along a route. Although need for information pertaining to the close environment of the car is obvious, so far no intervehicle communications system for data exchange between vehicles and between roadside and vehicles has been put into operation. To promote the development of such an inter-vehicle communication system, the project “FleetNet – Internet on the Road” was set up by a consortium of six companies and three universities: DaimlerChrysler AG, GMD FOKUS, NEC Europe Ltd., Robert Bosch GmbH, Siemens AG, TEMIC TELEFUNKEN microelectronic GmbH, Universities of Mannheim and Hannover, and Technische Universität Hamburg-Harburg. The project is partly funded by the German Ministry of Education and Research. FleetNet started on September 1, 2000 and will end on December 31, 2003. FleetNet aims at the development and demonstration of a wireless ad hoc network for inter-vehicle communications. Key design requirements for FleetNet are the capability to distribute locally relevant data where generated and needed and to satisfy the vehicle drivers’ and passengers’ needs for location-dependent information and services. Location awareness and position data play a crucial role not only for FleetNet applications but also for the communication protocols deployed. This paper provides an overview of the FleetNet project: we describe FleetNet applications and services as well as Fleetnet’s technical challenges together with our current design choices.

Internet on the Road via Inter-Vehicle Communications

Method for avoidance of collisions amongst road traffic wherein signals transmitted by an inter-vehicle communication system are detected and if a vehicle is approaching with a critical velocity, a reaction is triggered in both of the concerned vehicles. Independent claims are made for: a collision avoidance warning device, with a receiver that detects signals from other vehicles in an inter-vehicle communication system and analyses them to detect a critical approach of another vehicle in order to trigger a warning in both the concerned vehicles; and a method for generation of a security zone around a number of moving vehicles that are transmitting inter-vehicle communications signals. The zone can be extended to creation of an electronic buffer zone along the edges of pavements, etc. that generates a warning to pedestrians, cyclists, etc.

Collision avoidance system for use by motor vehicles equipped with an inter-vehicle communications system so that if a vehicle comes too close or is moving too quickly a warning is triggered in both of the vehicles involved

Walter Franz

Papers

Car-2-Car Communication Consortium - Manifesto

Inter-Vehicle-Communications - Based on Ad Hoc Networking Principles : The FleetNet Project

Performance measurements of a vehicular ad hoc network

Internet on the Road via Inter-Vehicle Communications

Collision avoidance system for use by motor vehicles equipped with an inter-vehicle communications system so that if a vehicle comes too close or is moving too quickly a warning is triggered in both of the vehicles involved