Analysis of wideband EMI field data

Last year, we reported on a preliminary evaluation of GE's frequency-domain EMI prototype sensor capable of measuring the wideband response of simulant and inert low metal mines at shallow depths over a frequency range from 100 Hz to 150 kHz. Since then, the prototype sensor has undergone further power and sensitivity improvements and has been taken to the field to collect signature data on targets in a calibration grid located at an Army facility in Virginia. The frequency-domain EMI responses have been analyzed by Duke University utilizing matched subspace detector (MSD) processing. The limited amount of data collected, so far, suggests that MSD processing of the frequency-domain data is a robust technique for target detection and identification. However, more data need to be collected for robust testing.