With the same type of fiber optic cables used in telecommunications systems, researchers from the Technion-Israel Institute of Technology have developed a way to detect and pinpoint the excavation of tunnels during times of war, such as those used for smuggling weapons into Gaza. The findings will be presented at the Defense, Security and Sensing Conference of SPIE (an international society advancing light-based research) in April 2009 in Orlando, Florida.
Principal researchers Dr. Assaf Klar and Dr. Raphael Linker, both of the Technion Faculty of Civil and Environmental Engineering, say the system is capable of locating even narrow tunnels at depths greater than 60 feet with a limited number of false alarms.
“Tunnel excavation is accompanied by the release of stresses that cause permanent – though very tiny – displacements and strains in the ground,” says Dr. Klar. “If you can measure these strains in the soil with sensitive equipment, you can find the tunnel’s location.” Tunnel excavation has a distinctive signal that is very different from those of disturbances, he adds.
The research lays the groundwork for the initial stages of an underground fence based on an existing technology called BOTDR (Brillouin optical time domain reflectometry) that makes it possible to measure fiber distortion along 15 miles using one device.
The proposed system is based on “wavelet decomposition” of the continuous BOTDR signal, a process that breaks down the signal profile into simpler shapes, and then filters out any irrelevant signals (“noise”). The signals that remain are then characterized by a neural network that has been trained to locate tunnels using computer simulation of tens of thousands of profiles, including disturbances not related to tunneling (examples include raindrops).
“The ability of the BOTDR approach to supply a continuous profile of soil distortions along the fiber optic line – and the ability of the neural network to identify the relevant profile that characterizes the excavation – are the keys to the system’s success,” says Dr. Linker.
The Technion-Israel Institute of Technology is Israel's leading science and technology university. Home to the country’s winners of the Nobel Prize in science, it commands a worldwide reputation for its pioneering work in nanotechnology, computer science, biotechnology, water-resource management, materials engineering, aerospace and medicine. The majority of the founders and managers of Israel's high-tech companies are alumni. Based in New York City, the American Technion Society (ATS) is the leading American organization supporting higher education in Israel, with 22 offices around the country.
Kevin Hattori | Newswise Science News
Snake-inspired robot uses kirigami to move
22.02.2018 | Harvard John A. Paulson School of Engineering and Applied Sciences
Camera technology in vehicles: Low-latency image data compression
22.02.2018 | Fraunhofer-Institut für Nachrichtentechnik, Heinrich-Hertz-Institut, HHI
Quantum computers may one day solve algorithmic problems which even the biggest supercomputers today can’t manage. But how do you test a quantum computer to...
For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.
In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...
Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale
Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...
For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.
But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...
Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.
The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...
15.02.2018 | Event News
13.02.2018 | Event News
12.02.2018 | Event News
22.02.2018 | Life Sciences
22.02.2018 | Physics and Astronomy
22.02.2018 | Earth Sciences