Course Description

The MUSICS Graduate School is pleased to announce a talk on 

Localization in asynchronous wireless networks : from theory to experiments

Given by François Quitin, Assistant Professor at Université Libre de Bruxelles (ULB), Belgium 

March 7th, 10:30, Shannon room (A105), Maxwell Building, Place du Levant 3, 1348 Louvain-la-Neuve

In this talk we discuss new approaches and strategies to achieve localization in wireless networks. Localization in wireless networks typically requires expensive or dedicated wireless infrastructure: a network of synchronized nodes to perform time-of-arrival (TOA) estimation or a multi-antenna array to perform angle-of-arrival (AOA) estimation, etc. The methods presented in this talk aim at achieving AOA or TOA estimation using mobile, single-antenna receivers, augmented with sensing devices that are readily available in consumer electronics.

We first consider the problem of AOA estimation of a RF transmitter using a mobile receiver. By considering the phase of successive packets received along the receiver trajectory, we implicitly create a virtual MIMO array, which allows us to utilize conventional MIMO theory for AOA estimation. Two main challenges need to be overcome for this method to work: 1) we must separate the phase offset due to receiver movement from the phase offset due to local oscillator offset; and 2) we must estimate the receiver’s position within a fraction of a wavelength. We will see how simple estimation methods and integration of IMU sensors allow us to meet both of these objectives. Experiment results with a software-defined radio testbed are presented that validate the proposed method.

The second problem we consider is that of a periodic RF transmitter localization using TOA information. The receiver measures the TOA of the periodic messages at different locations along its trajectory. By comparing the TOA of successive messages at different points along its trajectory, the receiver can eventually estimate the transmitter location. The challenge lies in separating the time offset due to receiver movement from that caused by local oscillator (LO) drift. We propose an extended Kalman filter framework that estimates the LO drift and the transmitter location simultaneously, using the TOA measurements and the receiver location as inputs. The proposed algorithm is implemented and tested on a software-defined radio testbed, and experimental results demonstrate the effectiveness of the proposed method.

Short Biography

François Quitin is an Assistant Professor at the Université libre de Bruxelles (ULB).  He received his PhD from ULB and UCLouvain in 2011; his thesis dealth with wireless channel models for polarized MIMO systems.  From 2011 to 2013, he was a postdoc at the University of California, Santa Barbara (UCSB) where he worked on distributed MIMO systems and robotic wireless networks.  From 2013 to 2015, he was a research fellow at Nanyang Technological University (NTU), Singapore, where he worked on localization techniques in robotic wireless networks.  His research interest focus on proof-of-concept and embedded system design for communication systems, taking advanced theoretical ideas all the way to practice.

Registration : free and requested on Musics website :

http://sites.uclouvain.be/doctoralschool-musics/CoursesList?view=item&id=318514401