Combined Electromagnetic and Magnetometer Data Acquisition and Processing
Abstract
In unexploded ordnance (UXO) detection demonstrations at Jefferson Proving Ground (JPG) and other places, active electromagnetic induction (EM) technology and magnetometry have consistently demonstrated the best UXO detection capabilities. Clearly, UXO site characterization is normally best accomplished using both EM and magnetometry, as each technology brings a complementary detection and discrimination capability; magnetometers typically perform better for large, deep ferrous objects, and EM sensors such as the Geonics EM61 typically perform better for small, shallow objects of all metals. However, simultaneous deployment of these two technologies on a single platform is difficult due to the active nature of electromagnetic induction technology, which generates noise that is picked up by magnetometers operated at close proximity. As economics often restrict site characterization technology to only one survey, this constraint leads most often to the down-selection and use of only one technology. Occasionally, sequential surveys with different sensors are employed but with attendant higher survey costs and added safety/risk exposures. Thus, for reasons of performance, economy, and safety, a single-platform magnetometer and EM61 solution would be widely used, if it existed. Under this project, GEO-CENTERS and the U.S. Army Corps of Engineers developed and demonstrated a proof-of-concept synchronized data acquisition and processing system that allows simultaneous deployment of both EM61 and magnetometer sensors on a single vehiculartowed platform. New sampling electronics were designed and developed that interleave the magnetometer and the EM61 data, sampling the magnetometers only after the EM61 pulse has diminished, thereby eliminating EM61-induced noise on the magnetometers.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 2005
- Accession Number
- ADA603940
Entities
People
- Alan Crandall
- Rob Siegel
- Roger Young
Organizations
- Environmental Security Technology Certification Program