This theme is dedicated to location and communication systems for safety in road and rail transportation.
The work targeted by this theme is mainly focused on the physical layer of wireless transmission systems for intelligent transportation. The main topics addressed are:
- Localization system by ultra wide band technique (RT localization, 3D localization, Localization and communication system for guided transport
- Radar techniques for obstacle detection, recognition and tracking
- High speed communication systems for HSR (High mobility): supervised channel estimation techniques for LTE or WiMax type links
- V2V communication systems
- Radio cognitive systems for rail communications
The main recent research topics
- Complete study from simulation to realization of the real-time embedded system on FPGA platform
- Field testing in the Val de Lille
- Adaptive throughput and robust communication link
- Original CPM/2pM multiplexing methods.
- Range (600m to 1km) and throughput approaching 22 Mbps
Example of the work carried out: Implementation of an anti-collision radar for road vehicles that is able to detect the nature of the obstacle (motorcycle, bicycle, pedestrian, highway curb, ...) for better accident prevention. Within the framework of the ANR project "PRIMACARE" labeled ITrans, the designed radar system signals to the driver the obstacles perceived on 360°, by means of spatialized alarms (3D sound)..
The system encompassing the achievements of all project partners (A-Volute, UPHF-LAMIH and LEOST-IFSTTAR) was the subject of a demonstrator in March 2012 showing the performance of this concept. The following figure shows the vehicle we equipped to test the proposed algorithms.
Fig. vehicle equipped as part of the PRIMACARE project:
Tracked detection and rendering of obstacles
One of the components studied in the PRIMACARE project consists in developing a UWB radar whose main advantages:
- Good range resolution (qcq cm)
- Ability to detect the type of obstacles 'decrease in false alarm rate'
- FPGA architecture for real-time computing at 3GHz
- Filing of a patent (following the ANR PrimaCare project)
PRIMACARE project concept: ULB radar-based obstacle detection and identification
4G wireless communication systems (LTE, IEEE.802.16e and IEEE.802.20) are being developed in the railroad world to provide information services, maintenance services, seat reservation services or Internet access. The consequences of the Doppler effect on the performance of such systems are important.
Our work is to propose solutions to minimize these degradations. It focuses on an efficient estimation of a time-varying channel in an OFDM system. In order to estimate the channel, which is essential for data equalization, pilots are inserted into the OFDM symbol.
The channel is estimated in the time domain and the time variations of each channel path is modeled by a basis function expansion (BEM Basis expansion Modeling), thus, the channel is obtained by the corresponding basis coefficients. A pilot structure is proposed, which consists in varying the pilot positions from one symbol to another. The pilot positions are dynamically allocated during the transmission of OFDM symbols.
This is referred to as dynamic pilot allocation (DPA). The time-varying channel estimation is better and therefore the system performance is improved compared to the Doppler effect. In a multiuser OFDM system, we propose to exploit the idea of ADP to create spatial diversity.
Each user is designated by a unique driver combination. By using cooperation among different users (spatial diversity), the estimation of the time-varying channel is improved and the consequences of the Doppler effect are reduced.
Recent developments in digital electronics and telecommunications have accelerated the realization of several systems dedicated to transportation especially for safety and comfort aspects. Hence the need to move from a few Mbits/s link to links that can reach several Gbits/s and thus allow a multitude of future applications. Our technological challenge is to reach the desired throughput of the order of Gbit /s, using UWB signals.
In addition, ultra-wideband propagation is said to be favorable, as it can minimize the detrimental role of fading, and it improves the link budget compared to conventional low-band modulations. Indeed, it is in this context that the ULB technology initially used in radars was considered for very high speed wireless communications over short distances.
In this context we have proposed a new modulation named M-OAM allowing the increase of the throughput and the improvement of the robustness of an IR-UWB system with good BER performances.
Other work in this group is dedicated to broadband wireless communications.
Intelligent transportation systems play an important role in the railway field.
The aim of this work is, the study and design of a cooperative radar system, which allows the detection and identification of obstacles on the tracks, the localization of trains, and the transmission of train-infrastructure data, while basing ourselves on ultra broadband technology to be able to ensure a good localization quality and a high transmission rate without interfering with existing systems.
Study framework: CPER CISIT COLOR project and Tarik TAHRI's thesis
. Subject: multimode cooperative radar systems for detection, identification of obstacles on tracks, localization and transmission of train-infrastructure data.
Supervisors: A.RIVENQ, Y.ELHILLALI
In this framework, we propose to develop a train-to-train localization and communication system based on a secure software platform capable of ensuring system safety and reliability at unprecedented levels. It is a system capable of offering, within a single module, two functionalities, localization and communication between trains in various environments encountered.
Various multiple access techniques will be developed to provide train-to-train or train-to-infrastructure localization and communication with good performance in terms of throughput, range, and transmission reliability. We plan to provide a mechanism to define the process chain (transformation, verification, ...) needed to produce low-level models from high-level models.
The proposed communication and localization system will be simulated, tested in real operating conditions. This project has the potential to greatly improve transportation safety, and is crucial to maintaining a technological advance in the region.
The applications requiring location systems are numerous (Transport, Tourism, Health, Aeronautics, Factories, Mines, ...). The use of space techniques, such as geo-positioning by GPS, for civilian applications has been common for several years; but are limited in terms of accuracy in indoor environments.
Breaking with commonly used techniques in order to minimize the constraints of the propagation environment, the use of Ultra Wide Band (ULB) technology can effectively address these new needs. The objective of this work is to study, develop and test a localization system based on this technology and in particular the realization of 3D localization techniques.
Framework of the study: thesis of Mr K. Ignace. KOSSONOU
. "3D high precision localization system based on ULB transmission techniques with low energy consumption for communicating mobile communicating objects.
Supervisors: A. RIVENQ, J. ASSAAD, Y. EL HILLALI, M. BOCQUET, I. DOUMBIA.
Work in progress - Prospects
We are continuing our research on the realization of real-time processing for ULB communicating radar systems, especially on FPGA circuits. The challenge being to realize computations at frequencies higher than 1 GHz. This type of signals is able to pass through walls, we have started a series of tests in order to evaluate the radar performance in terms of recognition of detected objects..
- Alstom, Bombardier, Thales, A-Volute, Effidence, Télécoms Brest, IFFSTAR, University of Kent, University of Essex, University of Sfax, cadi ayyad university in marrakech, Mohammed V University Rabat