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One of the essential usage of Intelligent Transportation Systems (ITS) applications is to provide road traffic information to vehicle drivers for road safety and efficient drive. For this usage, it is necessary to integrate geographical routing mechanisms in vehicular ad hoc network (VANET) into ITS applications. In this paper, we design and implement an ITS application which relies on IPv6 GeoNetworking;...
Road traffic congestion in urban areas and metropolitan cities is becoming nowadays an increasingly critical issue. With the advances in wireless technologies and the emergence of vehicle to vehicle communication techniques, new research studies are carried out to develop new applications and services over vehicular ad hoc networks for road safety and road traffic management. In this paper we present...
This paper presents a double directional analysis of vehicle-to-vehicle channel measurements conducted in three different traffic scenarios. Using a high- resolution algorithm, we derive channel parameters like Angle-of-Arrival (AOA), Angleof- Departure (AOD), propagation delay and Doppler shift and identify underlying propagation mechanisms by combining these estimates with maps of the measurement...
An efficient medium access control (MAC) protocol should yield maximum throughput and fairness. However, because these two performance metrics have conflicting interests, an effective solution must address the trade-off between them. In this paper, we study the performance of the IEEE 802.11p MAC protocol in vehicle-to-infrastructure communications. The main focus is the trade-off between the system...
The wireless access in vehicular environment (WAVE) architecture of intelligent transportation system (ITS) has been standardized in the IEEE 802.11p specification and it is going to be widely deployed in many roadway environments in order to provide prompt emergency information and internet services. A typical WAVE network consists of a number of WAVE devices, in which one is the road-side-unit (RSU)...
Intelligent Transport Systems envision many applications relying only on vehicle-to-vehicle communications. Depending on the application (road safety, driver information, infotainment...), the requirements are different in terms of throughput, delay and loss rate. This paper explores the performances issues of a convoy of vehicles on the road, in order to estimate the capacity of such linear vehicular...
Vehicular networking is nowadays very hot topic within the research field of telecommunications. Lot of different approaches exist, although the standard approach called IEEE 802.11p is gaining the majority of interest. Even if IEEE 802.11p seems to be the main approach, the operability in real conditions has not yet been under careful consideration. This paper presents the vehicular networking simulations,...
This paper deals with cooperative reconstruction of environmental variables (e.g., temperature) along a road by a vehicular sensor network using wireless communication. Vehicles take repeated measurements and approximate the environment using a set of basis functions. We investigate the applicability and performance of popular averaging techniques (gossiping and consensus propagation) on the basis...
Efficient vehicle-to-Internet routing and address autoconfiguration are two of the missing pieces required to provide Internet connectivity from vehicles. Here, we propose TREBOL, a tree-based and configurable protocol which benefits from the inherent tree-shaped nature of vehicle to Internet traffic to reduce the signaling overhead while dealing efficiently with the vehicular dynamics. The paper...
The VANET are mainly characterized by the high nodes velocity, high nodes density at road intersections and traffic jams and severe radio signals degradation caused by obstacles present in the external environment. This make the direct application of routing protocols defined for MANET not suitable for VANET. In this paper we consider a simulation environment representing a real city map with its...
In this paper, we evaluate how traffic-load dependent vehicle routing at intersections is able to improve the connectivity status of all streets. To this end, we consider a VANET scenario, comprised of several streets and intersections. Then, we focus on two vehicle routing algorithms, one based on the distance to destination, i.e., traffic-load independent (TLI) algorithm, and another one based on...
We investigate the problem of adaptive traffic light control of multiple intersections using real-time traffic data collected by a wireless sensor network (WSN). Previous studies mainly focused on optimizing the intervals of green lights in fixed sequences of traffic lights and ignored the traffic flow's characteristics and special traffic circumstances. In this paper, we propose an adaptive traffic...
Dedicated Short Range Communication (DSRC) is a promising technique for vehicle ad-hoc network (VANET) and collaborative road safety applications. As road safety applications require strict quality of services (QoS) from the VANET, it is crucial for DSRC to provide timely and reliable communications to make safety applications successful. In this paper we propose two adaptive message rate control...
Vehicular networking has significant potential to enable diverse range of applications, including safety and convenience. As the number of vehicles and applications using wireless spectrum grow, one can expect to see a shortage of either spatially or temporally available spectrum. In this paper, we advocate that dynamic spectrum access for vehicles be the first step towards solving the spectrum shortage...
In current transport logistics, routing is usually performed centrally. This paper presents a novel approach introducing dynamic transfer nodes and a distributed decision process to redeploy transport objects. Thus, transportation vehicles, such as buses, operate autonomously and communicate among each other to optimise the redistribution of their current passengers. Because the system works without...
In this paper, we present a measurement study of application layer performance in IEEE 802.11p vehicular networks. More specifically, our focus is on active safety applications, which are based on the exchange of beacon messages containing status information between close-by vehicles. We consider two performance metrics relevant to active safety applications: the first is application-layer goodput,...
Abstract - High-speed mobility has been a central issue to telecommunication in both theory and practice. Each generation of technology presents unique design and engineering challenges in products and deployments. It is especially critical to a class of upcoming 4G (4th-Generation) mobile broadband systems because of broader spectrum usage, aggressive modulation schemes, and sophisticated adaptation...
In high-speed mobile OFDM communication systems, receiving characteristics degrade significantly due to time variation of the channel properties. One solution is to rotate a circular array antenna so as to decrease the speed of receiving antenna relative to the ground [1]. When the vehicle speed changes, the rotating antenna needs to keep the optimum rotation speed. To solve this problem, we proposed...
In urban scenarios traffic signal controls are the main mechanism to control vehicular flow at the intersections. However, traditional systems fail to adjust the timing pattern in accordance to the time variability. An alternative to such systems is to develop dynamic systems which will alter the timing patterns according to the traffic demand. In this paper, an adaptive traffic signal control system...
In this paper the behavior and the self-optimization of an LTE network under realistic conditions are investigated. To enhance network performance in a urban environment a controller to auto-tune parameters has been proposed. An urban mobility model has also been defined in order to test the proposed method under realistic conditions. This model allows to investigate some performance features, wich...
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