Determining tunnel positions under rough surfaces with underground focused synthetic aperture radar

IEEE AP-S Boston Chapter is pleased to present this fascinating talk on determining tunnel positions using underground focused SAR. As you can guess, this technology has many relevant applications.

Feel free to invite your colleagues, we are looking forward to seeing you there;

6:00 PM, Tuesday, 8 June

Determining tunnel positions under rough surfaces with underground focused synthetic aperture radar

Carey Rappaport, Northeastern University, Boston, MA 02115

Underground tunnels present both military and homeland security threats since smugglers use them as transit routes for trafficking weapons, explosives, people, drugs, and other illicit materials. Detecting and imaging the presence of tunnels in any given region of ground is possible because the air that fills them is materially quite different from anything else underground. The Spotlight Synthetic Aperture Radar (SL-SAR) has been used due to its ability to scan large areas of terrain in a short amount of time, which is ideal for tunnel detection. In order to obtain strong and distinct target signals, Underground Focusing, based on ray refraction at the ground surface is being considered. This presents a challenge since the technique requires an estimation of the ground characteristics, and the random roughness of the soil surface tends to distort the reconstructed image of the analyzed geometry.

This presentation explores the impact of the surface roughness in Underground Focusing SAR imaging for tunnel detection applications. The study starts by simulating incident plane waves from 19 angles (-45 to 45 degrees) at 128 different frequencies (55 to 550 MHz) with 2-D Finite Difference Frequency Domain (FDFD) analysis on 2 different types of soil: non-dispersive sandy soil and lossy clay loam soil with 10 cm of randomly distributed roughness. It is demonstrated that a shallow tunnel can be imaged in low moisture, non-conductive sand, but that the more lossy moist clay presents too much surface clutter to distinguish the tunnel.

Carey M. Rappaport (IEEE M, SM 96, F 06) received five degrees from the Massachusetts Institute of Technology: the SB in Mathematics, the SB, SM, and EE in Electrical Engineering in June 1982, and the PhD in Electrical Engineering in June 1987. He is married to Ann W. Morgenthaler, and has two children, Sarah and Brian.

Prof. Rappaport has worked as a teaching and research assistant at MIT from 1981 until 1987, and during the summers at COMSAT Labs in Clarksburg, MD, and The Aerospace Corp. in El Segundo, CA. He joined the faculty at Northeastern University in Boston, MA in 1987. He has been Professor of Electrical and Computer Engineering since July 2000. During fall 1995, he was Visiting Professor of Electrical Engineering at the Electromagnetics Institute of the Technical University of Denmark, Lyngby, as part of the W. Fulbright International Scholar Program. During the second half of 2005, he was a visiting research scientist at the Commonwealth Scientific Industrial and Research Organisation (CSIRO) in Epping Australia. He has consulted for CACI, Alion Science and Technology, Inc., Geo-Centers, Inc., PPG, Inc., and several municipalities on wave propagation and modeling, and microwave heating and safety. He was Principal Investigator of an ARO-sponsored Multidisciplinary University Research Initiative on Humanitarian Demining, Co-Principal Investigator of the NSF-sponsored Engineering Research Center for Subsurface Sensing and Imaging Systems (CenSSIS), and Co-Principal Investigator of the DHS-sponsored Awareness and Localization of Explosive Related Threats (ALERT) Center of Excellence.

Prof. Rappaport has authored over 330 technical journal and conference papers in the areas of microwave antenna design, electromagnetic wave propagation and scattering computation, and bioelectromagnetics, and has received two reflector antenna patents, two biomedical device patents and three subsurface sensing device patents. He was awarded the IEEE Antenna and Propagation Society's H.A. Wheeler Award for best applications paper, as a student in 1986. He is a member of Sigma Xi and Eta Kappa Nu professional honorary societies.

Meeting will be held at MIT Lincoln Laboratory A-Café, 244 Wood Street, Lexington, MA. For directions please see:http://www.ll.mit.edu/about/map.html

For more information, contact Antennas & Propagation chair, Gregory Charvat at Gregory.charvat@ll.mit.edu