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A pervasive sensor network, under and above all of us

Million of miles of fibre optics cables are laying in the ground and they can be used to monitor what’s going on above them. Image credit: Lawrence Manning, Getty Images, Wired

That the telecommunications network can be used as a gigantic, and pervasive, sensor is not a news. As an example the mobile network has to track the movement (and position) of cellphones to be able to connect them. Get those data and you can have a very accurate map of traffic in a city, analyse those data and you can “learn” the habits of a population down to a single individual and then you can predict what might happen next.

Several years ago (and technology has evolved enormously since that time) Telecom Italia, Ericsson and MIT’s Senseable cities worked together to show the potential of the mobile network to provide the pulse of Rome in Italy. The trial was made in such a way to protect the privacy of everybody, yet even through the use of anonymised data it was possible to see what was going on in the city.

Technology can be used to analyse the tiny variation of a WiFi electromagnetic field to detect presence and movement of people inside a home from the outside. Artificial intelligence can be used to analyse the field variation.

Now an article on Wired is reporting a study made by researchers at Penn State University showing how fibre networks can be used to detect movement of cars and people happening to drive/walk in the vicinity of the fibre.

Fibre networks are (mostly) running underground, a yard or less below the tarmac. Driving and walking generates tiny vibrations that in turns alter the propagation of the laser signals flowing in the fibre. The alteration does not affect the signal (the message coded) but can be detected and analysed using artificial intelligence (spiced with machine learning to “learn” the specific characteristics of the effect in that portion of the network).

The study showed that people walking create vibration in the range of 1-5Hertz whilst cars generate vibrations in the 50 Hertz range. Heavy machinery generate vibrations in the 100 Hz range.

What is amazing from the study is the resolution that can be achieved: alterations can be localised with a precision of 2 meters (6 feet and a half). It is like having thousands of sensors picking up activities above ground.

A city can use these data to monitor traffic, a factory can use them to monitor the operation of machines (creating a digital signature) detecting anomalies as they happen.

Interesting stuff!

About Roberto Saracco

Roberto Saracco fell in love with technology and its implications long time ago. His background is in math and computer science. Until April 2017 he led the EIT Digital Italian Node and then was head of the Industrial Doctoral School of EIT Digital up to September 2018. Previously, up to December 2011 he was the Director of the Telecom Italia Future Centre in Venice, looking at the interplay of technology evolution, economics and society. At the turn of the century he led a World Bank-Infodev project to stimulate entrepreneurship in Latin America. He is a senior member of IEEE where he leads the New Initiative Committee and co-chairs the Digital Reality Initiative. He is a member of the IEEE in 2050 Ad Hoc Committee. He teaches a Master course on Technology Forecasting and Market impact at the University of Trento. He has published over 100 papers in journals and magazines and 14 books.