Development of a man-portable room-temperature gradiometer--phase II: portable and fieldable prototype

In Phase II of a Small Business Innovation Research (SBIR) contract funded through the Office of Secretary of Defense (OSD), Quantum Magnetics is developing a fieldable room- temperature gradiometer (RTG). The RTG uses an innovative sensor configuration, called the three-sensor gradiometer (TSG), invented at IBM. The TSG affords unprecedented dynamic range that enables detection of signals near fluxgate sensor noise while the system is in motion int eh earth's field. Sensor enhancements undertaken in this Phase II program include: incorporation of ancillary sensors to enable gradiometer balancing in the presence of ambient field gradients; improved feedback linearity and use of a wideband reference fluxgate sensor to reduce motion noise; and improved filter matching between channels. Operational developments in progress include reduction of the sensor electronics package for man-portability and implementation of real-time operating and target localizing software. The Phase II system will be used for land-based operations to locate unexploded ordnance, and the sensor is being integrated with differential global position satellite navigation to locate targets in geographical coordinates. Separately funded programs will adapt the RTG for use by divers or AUVs in finding naval mines and obstacles.