DESIGN AND PERFORMANCE ANALYSIS OF A PORTABLE REAL-TIME THROUGH-WALL NOISE RADAR

Open Access
Author:
Chen, Pin-Heng
Graduate Program:
Electrical Engineering
Degree:
Doctor of Philosophy
Document Type:
Dissertation
Date of Defense:
August 05, 2010
Committee Members:
  • Ram Mohan Narayanan, Dissertation Advisor
  • Ram Mohan Narayanan, Committee Chair
  • James Kenneth Breakall, Committee Member
  • Julio Urbina, Committee Member
  • Karl Martin Reichard, Committee Member
  • William Kenneth Jenkins, Committee Member
Keywords:
  • noise radar
  • through-wall sensing
  • through-wall imaging
  • correlation technique
  • active circulator
Abstract:
The development of through-wall surveillance (TWS) technology started in the 1980s to assist in searching for survivors after natural disasters. Recently, significant endeavors have expanded the application of this technology to anti-terrorism, law enforcement, and security operations. As a result, the purpose of TWS technology is not only limited to detect signs of life, but also to range and to image the targets behind walls. In this work, a digital real-time through-wall random noise radar has been successfully developed and integrated with an empirical mode decomposition (EMD) based micro-Doppler estimation as a single portable multifunction radar system. Extension of the existing theories on the wall distortion compensation, the radar operating principles, and practical considerations on the system operation have been developed. Experiments on one-dimensional ranging, two-dimensional imaging, and human micro-Doppler detection were conducted which not only validates the theories developed in this work but also demonstrates the system’s capability both at short and long stand-off distances. On the other hand, since the random noise signals generated by a thermal noise source are featureless, they are inherently difficult to be interfered with and not prone to interfere neighboring system. This is also demonstrated in this work. Last but not least, theories and prototypes of high-speed operational amplifiers based circulator were also developed in this work as a key component for shrinking the size of the system. In summary, the system confirms that noise radar technology combined with modern digital signal processing approaches is indeed a viable technique for covert ranging, imaging of obscured stationary and moving targets as well as to distinguish human activities via micro-Doppler detection.