Post-doctoral researcher in acoustic sensing over optical fiber networks at Télécom Paris - 12 months

Job description

Who are we?

A school of the Institut Mines-Télécom, Télécom Paris is the leading French school for generalist digital engineers. With its excellent teaching and research, Télécom Paris is at the heart of a unique innovation ecosystem based on the transversality of its training, its research departments and its business incubator.

A founding member of the Institut Polytechnique de Paris, Télécom Paris is positioned as an open-air laboratory for all the major technological and societal challenges.



SCIENTIFIC CONTEXT

The concept of a smart city relies on the collection and exploitation of data extracted by many sensors delivering information on circulation of vehicles, detection of human presence and many events affecting the infrastructures (water and gas networks, buildings, bridges and tunnels…). The current approach to collect this information is to deploy a multitude of discrete and dedicated sensors or deploy dedicated distributed optical fiber sensing cables. This deployment has a high logistical cost (installation, energy supply, maintenance). However, telecom fiber optic networks already crisscross current cities: the use of this available infrastructure for the purposes of capturing, locating and identifying vibration events is a very attractive approach. Most of the research works targeting sensing through the telecom infrastructure have replicated distributed acoustic sensing (DAS) solutions, originally used over dedicated sensing cables. They had shown promising results in road/rail traffic supervision [1-3] and in measuring dynamics on the scale of an urban or regional area: near-surface characterization [4-5] detecting high levels of use of certain sites during crisis (as in the current COVID19 crisis) [6-7], and other seismic events.

In DAS and geophysics workshops, researchers regularly highlight that DAS measurements over deployed optical fiber infrastructure are able to provide information on vibrations that are not detectable with conventional discrete sensors such as geophones or seismometers. Despite this positive observation, we believe that sensing through the deployed fiber cables can be drastically improved. The integration of powerful sensing techniques to the network will pave the way for enhanced real-time network monitoring and the provision of valuable data for a multitude of applications.


WORK PLAN

DAS approach relies on the existence of distributed Rayleigh backscattering, an inherent impairment in an optical fiber. The scientific barrier is mainly the low level of Rayleigh backscattering and its randomness. In an optical network, technical barriers also come from the heterogeneity of their topologies. For instance, the presence of multimode fibers in some legacy local area networks induce crosstalk among multiple propagating modes that might affect DAS sensitivity. In metropolitan networks, some optical devices can prevent the backscattering generated by the following fiber cables from reaching the interrogator (isolators, routing nodes…). In access networks, the existence of 1-to-N fiber topology (one fiber splitting to N through an optical splitter to serve N end-users) will lead to a localization ambiguity. The resolution of these problems will be at the heart of this project.

We propose to benefit from the deployed optical transmission infrastructure as a network of passive sensors to facilitate the telemetry of a large set of acoustic and vibratory phenomena reaching this infrastructure. Fiber is increasingly deployed in urban and rural areas, often throughout road and rail development projects. FTTx (Fiber To The x=Home, Building,…) networks and local area networks (LANs) are also developing fast, bringing the fiber closer to homes and workplaces to ensure the best quality of transmission and highest data throughput. The reuse of the optical infrastructure, whether through DAS or other sensing techniques, as a distributed vibration sensor, converts it into a neuralgic network enabling the detection of vibrations that propagate via different layers separating the vibration source from the fiber core. Characterization and localization of these vibrations with the highest possible accuracy, followed by their identification using automatic learning algorithms, pave the way for network monitoring and 

provision of valuable data for a multitude of applications (road/rail traffic supervision, security, monitoring urban dynamics to detect hazards particularly in times of crisis…).

We expect to deliver proof-of-concepts of sensing solutions that can address various sensing scenarios while targeting:

  • Zero impact on the quality of service (QoS) of the telecom network;
  • Achieving higher sensitivity levels, or wider scope of detectable strains than the state-of-the art and appropriate spatial resolutions for these scenarios.
  • Validating our solutions over lab setups and possibly field trials.


JOB DESCRIPTION

To carry out research missions in the field of photonics

  • Carries out research missions within the framework of the Department's contracts in the field of optical communications and fiber optic sensors
  • Participates and ensures the realization of project deliverables

To ensure supervision and tutoring missions

  • Supervises student projects and engineering internships

To contribute to the reputation of the School, the Institut Mines-Télécom and the Institut Polytechnique de Paris

  • Publishes the results of his/her research work
  • Carries out presentations and conferences
  • Participates to creation of intellectual property (patents)
  • Maintains close relations with academic institutions, research centers and companies

Job requirements

Required skills, experience, and knowledge:

  • - The candidate must have successfully finished a PhD in Electrical Engineering, Optical Communications, Photonics or related domains.
  • - Knowledge of optical transmission systems and networks is necessary. Knowledge of digital signal processing algorithms involved in communication systems or optical fiber sensors is desirable.
  • Skills in DSP programming (through MATLAB or Python) are appreciated

Other abilities and skills:

  • Strong interest for applied research
  • Ability to work in a multi-cultural environment and to supervise interns and/or students during projects
  • Fluently speaking English


Candidates with the following qualifications may apply:

  • PhD or equivalent


Why join us?
You will work in a pleasant, green and accessible environment (especially for people with disabilities) only 20 km from Paris (RER B and C suburban train lines, proximity to major roads). You will benefit from many advantages (flexible working hours, possibility of telecommuting, proximity to sports facilities, concierge service, etc.).


Other information :

Application deadline: March 30, 2023
Type of job : 12 months fixed term contract
Full job description here.

The application should be include:

- a detailed CV

- a letter of motivation

- any element considered useful for the examination of the application

Scientific contact : Élie Awwad (elie.awwad@telecom-paris.fr)

Administrative contact : Hamidou Yaya Koné (hamidou.kone@telecom-paris.fr)


All our positions are open to people with disabilities.