CITI Talk: “Passive RADAR measurement using DVB-T receivers and Software Defined Radio processing”, Jean-Michel Friedt (Université de Besançon, FEMTO-ST lab), March 30th at 10:30am

Passive RADAR measurement using DVB-T receivers and Software Defined Radio processing

Jean-Michel Friedt (Université de Besançon, FEMTO-ST lab)

Abstract
We demonstrate the use of affordable DVB-T receivers used as general purpose software defined radio interfaces for collecting signals from a non-cooperative reference emitter on the one hand, and signals reflected from non-cooperative targets on the other hand, to map the range and velocity in a passive radar application. Issues include frequency and time synchronization of the DVB-T receivers, mitigated by appropriate digital signal processing relying heavily on cross-correlations.

Passive radar uses existing non-cooperative emitters as signal sources for mapping non-cooperative target range and possibly velocity. The attractive features of this strategy is the lack of dedicated broadband source for RADAR application, low cost from the use of existing emitters, and stealth since the operator is undetectable. This measurement technique has become accessible to the amateur with the availability of low cost receivers ideally suited for software defined radio processing. In the framework of passive radar applications, two receivers must be synchronized to record simultaneously the reference channel and the signal reflected by the targets: cross correlation will then finely identify the reference signal delay in the measurement signal and allow for target identification. In the case of moving targets, a brute force approach similar to Doppler compensation in GPS acquisition is applied for the cross correlation to coherently accumulate energy: the range-Doppler maps hint at the distance to the target and its velocity. Most interestingly, in the latter context, clutter (signals reflected from static targets) is separated from the moving target which becomes well visible even in a complex environment. In this presentation, we discuss the details of real time acquisition and signal post-processing for passive radar application, while addressing some of the challenges of diverting DVB-T receivers from their original application. While passive radar has been demonstrated with FM broadcast emitters, analog television emitters, or wifi, we shall here consider the broadband signal provided by digital terrestrial television broadcast signal.

Webpage

http://jmfriedt.free.fr/

CITI Talk: “The Proof of the Pudding is in the Eating: Using SDRs in Research”, Bastien Bloessl (Trinity College à Dublin, Connect centre), March, 29th at 10:00 am

The Proof of the Pudding is in the Eating: Using SDRs in Research

Bastien Bloessl (Trinity College à Dublin, Connect centre)

Abstract
Software Defined Radios (SDRs), i.e., freely programmable radios, are about to revolutionize wireless. Implementing the whole communication stack in software not only adds flexibility, but also allows for rapid prototyping of novel technologies. With a proof-of-concept implementation we can advance from pure simulative performance evaluation to a combined approach with real measurements. This backs up research and speeds up development, experimentation, and testing of new concepts. This talk will provide an overview of SDR use-cases and give ideas about how to use them for research and development.

Biography
Bastian Bloessl is a researcher at the CONNECT Center, Trinity College Dublin, Ireland’s Research Center for Future Networks and Communications, where he is funded through a Marie Skłodowska-Curie fellowship. He received his diploma in Computer Science from the University of Würzburg, Germany, in 2011. After his diploma, he started as a PhD student at the Computer and Communication Systems Group at the University of Innsbruck, Austria. In 2014, he moved with the group to Paderborn University, Germany, to continue his studies. In 2015, he won a FitWeltweit scholarship from the German Academic Exchange Service (DAAD), which funded a six-month stay in the research group of Prof. Mario Gerla at the Computer Science Department of the University of California, Los Angeles (UCLA). His research is focused on using software defined radio-based prototypes to assess the performance and robustness of vehicular and sensor networks.

CITI Talk: “Heavy tailed distributions characterisations and examples of applications in channel modeling”, Prof Nourddine Azzaoui (Université Blaise Pascal), 14h00 in TD-C

Title

Heavy tailed distributions characterisations and examples of applications in channel modeling

Speaker

Associate Professor Nourddine Azzaoui

Date

16th March 2018

Time/Place

14h00 in TD-C.

Abstract

Currently, we are witnessing the proliferation of wireless sensor networks and the superposition of several communicating objects which have an heterogeneous nature. The advent of Internet of Things networks as well as the increasing demand for improved quality and services will increase the complexity of communications and puts a strain on current techniques and models. Indeed, they must firstly adapt to the temporal and spatial evolution and secondly, they must take into account the rare and unpredictable events that can have disastrous consequences for decision-making. This talk provides an overview of the various spectral techniques used in litterature describe a communication channel having an impulsive behavior. This is mainly motivated by the historical success of interactions between probabilities, statistics and the world of communications, information theory and signal processing. The presentation will be divided into two parts: the first is devoted to the synthesis of various developments on alpha-stable variables and processes in a purely mathematical mind. The second part will be devoted to applications in the context of communications. The two sides will combine two fundamentally linked aspects: first, a theoretical approach, necessary for a good formalization of problems and identifying the best solutions. Secondly, the use of these models in real work of channel modelling.

PhD Defence: “Middleware and programming models for multi-robot systems”, Stefan-Gabriel Chitic, Vitrine/RobIot room, Chappe Building, 15th of March 2018, at 10h:30

Title

Middleware and programming models for multi-robot systems

Abstract

Despite many years of work in robotics, there is still a lack of established software architecture and middleware for multi-robot systems. A robotic middleware should be designed to abstract the low-level hardware architecture, facilitate communication and integration of new software. This PhD thesis is focusing on middleware for multi-robot system and how we can improve existing frameworks for fleet purposes by adding multi-robot coordination services, development and massive deployment tools. We expect robots to be increasingly useful as they can take advantage of data pushed from other external devices in their decision making instead of just reacting to their local environment (sensors, cooperating robots in a fleet, etc).

This thesis first evaluates one of the most recent middleware for mobile robot(s), Robot operating system (ROS) and continues with a state of the art about the commonly used middlewares in robotics. Based on the conclusions, we propose an original contribution in the multi-robot context, called SDfR (Service discovery for Robots), a service discovery mechanism for Robots. The main goal is to propose a mechanism that allows highly mobile robots to keep track of the reachable peers inside a fleet while using an ad-hoc infrastructure. Another objective is to propose a network configuration negotiation protocol. Due to the mobility of robots, classical peer to peer network configuration techniques are not suitable. SDfR is a highly dynamic, adaptive and scalable protocol adapted from Simple Service Discovery Protocol (SSDP). We conduced a set of experiments, using a fleet of Turtlebot robots, to measure and show that the overhead of SDfR is limited.

The last part of the thesis focuses on programming model based on timed automata. This type of programming has the benefits of having a model that can be verified and simulated before deploying the application on real robots. In order to enrich and facilitate the development of robotic applications, a new programming model based on timed automata state machines is proposed, called ROSMDB (Robot Operating system Model Driven Behaviour). It provides model checking at development phase and at runtime. This contribution is composed of several components: a graphical interface to create models based on timed automata, an integrated model checker based on UPPAAL and a code skeleton generator. Moreover, a ROS specific framework is proposed to verify the correctness of the execution of the models and to trigger alerts. Finally, we conduct two experiments: one with a fleet of Parrot drones and second with Turtlebots in order to illustrates the proposed model and its ability to check properties.

Jury

Prof. Abderrafiaa KOUKAM, Université de Technologie de Belfort-Montbéliard (Reviewer)
Prof. Philippe LALANDA, Université́ Joseph Fourier, Saint-Martin-d’Hères (Reviewer)
Prof. Noury BOURAQADI, Institut Mines-Telecom, IMT Lille Douai (Member)
Dr. Stéphanie CHOLLET, ESISAR, Valence (Member)
Prof. Olivier SIMONIN, INSA Lyon (Supervisor)
Dr. Julien PONGE, INSA Lyon (Co-Supervisor)