Landmine detection with nuclear quadrupole resonance

Abstract

Nuclear Quadrupole Resonance (NQR) technology for the detection of explosives is of crucial importance in an increasing number of applications. For landmine detection, NQR has proven to be highly effective if the NQR sensor is not exposed to radio frequency interference (RFI). Since strong nonstationary RFI in the field is unavoidable, a robust detection method is required. With the aid of reference antennas, a frequency domain LMS algorithm is applied to cancel the RFI in field data. An average power detector based on power spectral estimation algorithms is proposed and performance using both the periodogram and MUSIC algorithms is evaluated. The detection performance has been compared with that of a non-adaptive Bayesian detector. The experimental results show that, unlike the non-adaptive Bayesian detector, the average power detector provides perfect detection capability if the data segments involved in the collection process are sufficiently long. 0-7803-7536-X/$17.00 (C) 2002 IEEE 1552a 1575

Advances in the engineering of quadrupole resonance landmine detection systems

“…The unwanted RFI is to a significant degree rejected by the design of the QR coil, but is also measured independently by additional reference antennas. Data from the reference antennas is processed and used to remove RFI signals from the data collected by the QR detection coil 13,[20][21][22] . The RFI-mitigated signal is then analyzed to determine whether a mine is present.…”