Section: Scientific Foundations

V2V and V2I Communications for ITS

Participants : Thierry Ernst, Oyunchimeg Shagdar, Gérard Le Lann, Manabu Tsukada, Thouraya Toukabri, Satoru Noguchi, Ines Ben Jemaa, Mohammad Abu Alhoul, Fawzi Nashashibi, Arnaud de la Fortelle.

Wireless communications is expected to play an important role for road safety, road efficiency, and comfort of road users. Road safety applications often require highly responsive and reliable information exchange between neighboring vehicles in any road density condition. Because the performance of the existing radio communications technology largely degrades with the increase of the node density, the challenge of designing wireless communications for safety applications is enabling reliable communications in highly dense scenarios. Targeting this issue, IMARA has been working on medium access control design and visible light communications especially for highly dense scenarios. The works have been carried out considering vehicles' behavior such as vehicles' merging and platooning.

Unlike many of the road safety applications, the applications regarding road efficiency and comfort of road users, on the other hand, often require connectivity to the Internet. Based on our expertise in both Internet-based communications in the mobility context and in ITS, we are now investigating the use of IPv6 (Internet Protocol version 6 which is going to replace the current version, IPv4, in a few years from now) for vehicular communications, in a combined architecture allowing both V2V and V2I. In the context of IPv6, we have been tackling research issues of combinations of MANET and NEMO and Multihoming in Nested Mobile Networks with Route Optimization.

The wireless channel and topology dynamics are the characteristics that require great research challenge in understanding the dynamics and designing efficient communications mechanisms. Targeting this issue we have been working on channel modeling for both radio and visible light communications, and design of communications mechanisms especially for security, service discovery, multicast and geocast message delivery, and access point selection.

Below follows a more detailed description of the related research issues.

Multihoming in nested mobile networks with route optimization

Participants : Manabu Tsukada, Thierry Ernst.

Network mobility has the particularity of allowing recursive mobility, i.e. where a mobile node is attached to another mobile node (e.g. a PDA is attached to the in-vehicle IP network). This is referred to as nested mobility and brings a number of research issues in terms of routing efficiency. Another issue under such mobility configurations is the availability of multiple paths to the Internet (still in the same example, the PDA has a 3G interface and the in-vehicle network has some dedicated access to the Internet) and its appropriate selection.

Service discovery

Participants : Satoru Noguchi, Thierry Ernst.

Vehicles in a close vicinity need to discover what information can be made available to other vehicles (e.g. road traffic conditions, safety notification for collision avoidance). We are investigating both push and pull approaches and the ability of these mechanisms to scale to a large number of vehicles and services on offer.

Geographic multicast addressing and routing

Participants : Ines Ben Jemaa, Oyunchimeg Shagdar, Thierry Ernst, Arnaud de La Fortelle, Fawzi Nashashibi.

Many ITS applications such as fleet management require multicast data delivery. Existing works on this subject tackle mainly the problems of IP multicasting inside the Internet or geocasting in the VANETs. To enable Internet-based multicast services for VANETs, we introduced a framework that: i) to ensure vehicular multicast group reachability through the infrastructure network, defines a distributed and efficient geographic multicast auto-addressing mechanism and ii) to allow simple and efficient data delivery introduces a simplified approach that locally manages the group membership and distributes the packets among them.

Platooning control using visible light communications

Participants : Mohammad Abu Alhoul, Mohamed Marouf, Oyunchimeg Shagdar, Fawzi Nashashibi.

The main purpose of our research is to propose and test new successful supportive communication technology, which can provide stable and reliable communication between vehicles, especially for the platooning scenario. Although that VLC technology has a short history in comparing with other communication technologies, the infrastructure availability and the presence of the congestion in wireless communication channels are proposing VLC technology as reliable and supportive technology which can takeoff some loads of the wireless radio communication. First objective of this work is develop analytical model of VLC to understand its characteristics and limitation. The second objective of this work is to design vehicle platooning control using VLC. In platooning control, a corporation between control and communication is strongly required in order guarantee the platoon's stability (e.g. string stability problem). For this purpose we work on VLC model platooning scenario, to permit each vehicle the trajectory tracking of the vehicle ahead, altogether with a prescribed inter-vehicle distance and considering all the VLC channel model limitations. The integrated channel model to the main Simulink platooning model will be responsible for deciding the availability of the Line-of-Sight for different trajectory's curvatures, which mean the capability of using light communication between each two vehicles in the platooning queue, at the same time the model will calculate all the required parameters acquired from each vehicle controller.

Access point selection

Participant : Oyunchimeg Shagdar.

While 5.9 GHz radio frequency band is dedicated to ITS applications, there is not much known how the channel and network behave in mobile scenarios. In this work we theoretically and experimentally study the radio channel characteristics in vehicular networks, especially the radio quality and bandwidth availability. Based on our study we develop access point selection method to achieve high speed V2I communications.