Near Field Electromagnetics



The near-field electromagnetics (NFEM) research unit focuses on problems for which the far-field approximation can not be used and specific near-field phenomenons play an important role. This is the case for a large number of devices such as electrical motors, passive magnetic detectors, (gradiometers, magnetometers, …), electromagnetic induction sensors (EMI) (Metal detectors, wire detectors, …) and ground penetrating radars, especially when the antenna is used in close proximity to the soil.

Typical applications are landmine detection with metal detectors, explosive improvised device (IED) detection with wire detectors, marine mine detection with gradiometers, efficient electrical motor control including sensorless and fault-tolerant drives. From those typical applications it is clear that the NFEM knowhow is useful both for civil and military application. In our developments, our strategy is always to exploit the synergies that may exist between the military and civil domain.

Research projects


This project aims at developping a method based on a radio frequency radar to detect non destructively leaks in underground water transport networks. The involvement of RMA in the projects resides mainly in the image formation process of the volume below the ground surface based on radar measurements obtained through a ground penetrating radar method. Detection of water and other objects such as water pipes will also be tackled.


In a European Defence Agency framework, MRN16/Burmin aims at contributing to the definition of the future European Unmanned Maritime System, in order to detect and neutralize sea mines. RMA’s involvement resides in the inversion algorithms for the gradiometer and in the development of the fusion algorithms in order to combine the data from different sensors based on different technologies.


The aim of the project is to perform a detail study of methods to augment the tolerance of electric drives to faults. Both the detection of the faults and the reduction of the influence of these faults are considered, with as objective to maximize the performance of the motor in degraded mode.


This study aims at evaluating the added-value of a magnetic sensor to detect buried sea mines or other buried objects in a marine environment. Detection is based on the fact that the ambient magnetic field is slightly modified in the vicinity of a ferromagnetic object.


This project aims at studying control methods for permanent-magnet synchronous electrical motors. The so-called sensor-less control of the machine is in particular considered in order to eliminate one possible source of fault.

CEN - Organisation of a CEN workshop about "Characterization of soils for electromagnetic sensors"

To agree on which physical properties of the soil must be taken into account when studying and predicting the performance of metal detectors and ground penetrating radars;If possible a classification of soils with respect to their influence on detection could be agreed upon;Finally protocols for measuring these properties could be proposed.The output of this activity will be a CEN Workshop Agreement (CWA).

In a first phase RMA will write a draft Business Plan (BP) explaining the detailed goals and the way to achieve them.Then CEN workshop meetings will be organised where participants will approve a final Business Plan and find an agreement on the topics defined in it. RMA will chair this CEN workshop.


  1. Y. Yvinec. A survey of new tools to help clearing landmines and other explosive remnants of war. Lecture at Royal Higher Institute for Defence, 2016.
  2. Yann Yvinec and Pascal Druyts. Modelling of a command wire detector. In Proceedings of the 13th International Symposium Mine Action 2016, Biograd, Croatia, 2016.
  3. Eric Mersch, Pascal Druyts, and Xavier Neyt. Bayesian map fusion for target detection and localization. In URSI 2015 Benelux Forum, Enschede, the Netherlands, December 2015.
  4. Eric Mersch, Pascal Druyts, and Xavier Neyt. Sea mine detection using a magnetic gradiometer. In URSI 2014 Benelux Forum, Louvain-la-Neuve, Belgium, November 2014.
  5. Eric Mersch, Yann Yvinec, Yves Dupont, Xavier Neyt, and Pascal Druyts. Underwater magnetic target localization and characterization using a three-axis gradiometer. In OCEANS'14 MTS/IEEE, Taipei, Taiwan, April 2014.
  6. Martijn Nottebaere, Mohammad Reza Mahmoudzadeh Ardekani, Pascal Druyts, Sébastien Lambot, and Xavier Neyt. Automatic 3D subsurface pipe-detection and permittivity reconstruction from GPR measurements. In Proceedings of the 20th URSI Benelux Forum, November 2014.
  7. Eric Mersch, Yann Yvinec, Pascal Druyts, Xavier Neyt, and Yves Dupont. Marine buried mines detection using magnetic gradiometry. In Proceedings of the 8th International Marine Electromagnetics Conference (MARELEC 2013), Hamburg, Germany, July 2013.
  8. Y. Yvinec. On the Importance of Using Appropriate Test Protocols. In EOD Future in the Light of NATO EOD - Demonstration and Trials 2012: A Book of Papers, Tren v c in, Slovakia, 2012.
  9. Yann Yvinec. Comparing different gradiometer configurations for underwater survey and demining. In Proceedings of Symposium Humanitarian Demining 2012, Sibenik, Croatia, 2012.
  10. Yann Yvinec, Pascal Druyts, and Yves Dupont. Detection and Classification of Underwater Targets by Magnetic Gradiometry. In Proceedings of International Conference on Underwater Remote Sensing 2012, Brest, France, 2012.
  11. Pascal Druyts. Analysis of Environmental Effects on Electromagnetic Induction Sensors. PhD thesis, Royal Military Academy -- Université catholique de Louvain, Brussels and Louvain-La-Neuve, October 2011.
  12. Francesco Soldovieri, Olga Lopera, and Sébastien Lambot. Combination of Advanced Inversion Techniques for an Accurate Target Localization via GPR for Demining Applications. IEEE Trans. on Geoscience and Remote Sensing, 49(1):451-461, 2011.
  13. Yann Yvinec, Pascal Druyts, and Yves Dupont. Simulator Of Magnetometer And Gradiometer To Evaluate Detection And Classification Algorithms. In Poster for the 7th International Marine Electromagnetics Conference (MARELEC 2011), San Diego, USA, June 2011.
  14. P. Druyts, C. Craeye, and M. Acheroy. Volume of influence for magnetic soils and electromagnetic induction sensors. IEEE Transactions on Geoscience and Remote Sensing, 48(10):3686-3697, October 2010.
  15. Pascal Druyts, Yann Yvinec, and Marc Acheroy. A framework to relate soil properties to soil classes based on performance of metal detectors and dual sensors. In Y. Baudoin and Maki K. Habib, editors, Using Robots in Hazardous Environments, chapter 8, pages 189-218. Woodhead Publishing Limited, 2010.
  16. F Gabriel, F De Belie, P Druyts, and X Neyt. Strategy to detect and prevent the current zero-crossing for inverter powered drives. In The XIX International Conference on Electrical Machines - ICEM 2010, pages 1-6. IEEE, September 2010.
  17. Yann Yvinec and Pascal Druyts. A Simple Protocol For A Double-Blind Test On An Explosives/Drugs Long-Range Detector. In International conference dedicated to: Hazardous Materials: Issues Of Detection And Disposal, Koscierzyna, Poland, May 2010.
  18. P. Druyts, Y. Das, C. Craeye, and M. Acheroy. Modeling the response of electromagnetic induction sensors to inhomogeneous magnetic soils with arbitrary relief. IEEE transactions on geoscience and remote sensing., 47(1)(8):2627-2638, August 2009.
  19. F Gabriel, F De Belie, P Druyts, X Neyt, J Melkebeek, and M Acheroy. Compensating the influence of the stator resistor and inverter nonlinearities in signal-injection based sensorless strategies. In 2009 IEEE Vehicle Power and Propulsion Conference, pages 283-290. IEEE, September 2009.
  20. S Lambot, E Slob, J Rhebergen, O Lopera, K Jadoon, and H Vereecken. Remote estimation of the hydraulic properties of a sand using full-waveform integrated hydrogeophysical inversion of time-lapse, off-ground GPR data. Vadoze Zone Journal, 8(3):743-754, 2009.
  21. Yann Yvinec. Soil Properties And Performance Of Metal Detectors And Ground Penetrating Radars. In ASEM Seminar On New Technology For Demining And Human Security, Taranto, Italy, March 2009.
  22. Yann Yvinec, Pascal Druyts, and Marc Acheroy. A Simple Metal Detector Model to Predict the Probability of Detection in Landmine Detection. In Proc. of The UXO/Countermine/Range Forum 2009, Orlando, USA, August 2009.
  23. L Capineri, D. Daniels, P Falorni, O Lopera, and C G Windsor. Estimation of Relative Permittivity of Shallow Soils by Using the Ground Penetrating Radar Response from Different Buried Targets.. Progress in Electromagnetics Research Letters, 2:63-71, 2008.
  24. O Lopera. An Integrated Detection and Identification Methodology Applied to Ground-Penetrating Radar Data for Humanitarian Demining Applications. PhD thesis, Université catholique de Louvain, Belgium - École royale militaire, Belgium - Universidad de Los Andes, Colombia, 2008.
  25. O Lopera, N Milisavljevic, B Macq, and S Lambot. A parameter-estimation-based change detection methodology for landmine localization from ground-penetrating radar data.. In IGARSS 2008, Boston, Massachusetts USA, 2008.
  26. O Lopera, J Rhebergen, E Slob, N Milisavljevic, and S Lambot. Analysis of the effect of watering on landmine detection. In 12th International Conference on Ground Penetrating Radar GPR 2008, Birmingham,UK, 2008.
  27. Olga Lopera, Nada Milisavljevi, David Daniels, Alain Gauthier, and Benoît Macq. A time frequency domain feature extraction algorithm for landmine identification from GPR data. Near Surface Geophysics, 6(6):411-421, December 2008.
  28. E Slob, S Lambot, J Rhebergen, O Lopera, and H Vereecken. Closed loop hydrogeophysical inversion of time-lapse GPR data to determine hydraulic properties of a sandy soil. In SEG 2008, Las Vegas, Nevada USA, 2008.
  29. Yann Yvinec. An International Agreement On The Characterization Of The Effects Of Soils On Ground Penetrating Radars And Metal Detectors. In Progress In Electromagnetics Research Symposium (PIERS 2008), Hangzhou, China, March 2008.
  30. Yann Yvinec. Assessing Effects Of Soils On Metal Detectors And Ground Penetrating Radars. In Workshop On Soil Magnetism, Cranfield University, United Kingdom, August 2008.
  31. Olga Lopera and Nada Milisavljevic. Prediction of the effects of soil and target properties on the antipersonnel landmine detection performance of ground-penetrating radar: A Colombian case study. Journal of Applied Geophysics, 63(1):13-23, September 2007.
  32. O Lopera, N Milisavljevic, and S Lambot. Clutter Reduction in GPR Measurements for Detecting Shallowly Buried Landmines: a Colombian Case Study. Near Surface Geophysics, 2007.
  33. O Lopera, N Milisavljevic, B Macq, and S Lambot. Time-frequency domain signature analysis of GPR data for landmine identification. In Proceedings of the 4th International Workshop on Ground Penetrating Radar, pages 159-162, 2007.
  34. O Lopera, N Milisavljevic, J Rhebergen, and S Lambot. Analysis of the effect of target and soil properties on the detection performance of ground penetrating radar: experimental and in field results. In Proceedings of IGARSS 2007, Barcelona, Spain, 2007.
  35. Olga Lopera, Sébastien Lambot, and Nada Milisavljevic. Clutter reduction in GPR measurements for detecting shallow buried landmines : a Colombian case study. Near Surface Geophysics, 5:57-64, 2007.
  36. Olga Lopera, Evert Slob, Nada Milisavljevic, and Sébastien Lambot. Filtering soil surface and antenna effects from GPR data to enhance landmine detection. IEEE Trans. on Geoscience and Remote Sensingand Remote Sensing,, 45(3):707-717, 2007.
  37. I. V. D. Bosch. Accurate Modeling of Ground-Penetrating Radar for Detection and Signature Extraction of Mine-like Targets Buried in Stratified Media. PhD thesis, Catholic University of Louvain, Louvain-la-Neuve -- Royal Military Academy, Brussels, Belgium, January 2006.
  38. Pascal Druyts, Christophe Craeye, and Marc Acheroy. Comparing two methods to solve the layered sphere problem, application to electromagnetic induction sensors. In Proc. of The first European Conference on Antennas and Propagation (EUCAP2006), Nice, France, November 2006.
  39. Pascal Druyts, Yogadhish Das, Christophe Craeye, and Marc Acheroy. Effect of the soil on the metal detector signature of a buried mine. In Proc. SPIE Defence and Security Symposium, Orlando, FL, USA, April 2006.
  40. S Lambot, O Lopera, and E C Slob. Effect of the Antenna Height on the Estimation of the Soil Electromagnetic Properties using Full-Wave Inverse Modeling of GPR Data. In XI International Conference on Ground Penetrating Radar GPR 2006, Columbus, Ohio USA, 2006.
  41. O Lopera, S Lambot, E Slob, M Vancoolster, B Macq, and N Milisavljevic. A new integrated approach for characterizing the soil electromagnetic properties and detecting landmines using a hand-held vector network analyzer. In Defense and Security Symposium 2006, Orlando, Florida USA, 2006.
  42. O Lopera, N Milisavljevic, B Macq, and S Lambot. Change Detection Based on Parameter Estimation From Frequency-domain GPR Data for Demining Applications. In XI International Conference on Ground Penetrating Radar GPR 2006, Columbus, Ohio USA, 2006.
  43. I. van den Bosch, P. Druyts, M. Acheroy, and I. Huynen. Frequency and time-domain error in buried target radar signature extraction. In Proceedings of the Progress in Electromagnetics Research Symposium (PIERS), pages 251-255, Cambridge, MA, USA, March 2006.
  44. I. van den Bosch, P. Druyts, M. Acheroy, and I. Huynen. Numerical parametric study of buried target ground-penetrating radar signature. In Proceedings of SPIE Defence and Security Symposium, Orlando, FL, USA, April 2006.
  45. I van den Bosch, S. Lambot, P. Druyts, I. Huynen, and M. Acheroy. Buried target signature extraction from ground-penetrating radar signal. measurements and simulations. Near Surface Geophysics, 4(1):31-38, 2006.
  46. I. van den Bosch, S. Lambot, I. Huynen, M. Acheroy, and P. Druyts. Accurate and efficient modeling of monostatic GPR signal of dielectric targets buried in stratified media. Journal of Electromagnetic Waves and Applications, 20(3):283-290, 2006.
  47. S. Lambot, I. van den Bosch, B. Stockbroeckx, P. Druyts, M. Vanclooster, and E. C. Slob. Frequency dependence of the soil dielectric properties derived from ground-penetrating radar signal inversion. Subsurface Sensing Technologies and Applications, 6(1):73-87, January 2005.
  48. O Lopera, S Lambot, N Milisavljevic, B Scheers, and I van den Bosch. Background Subtraction in the Frequency Domain for Focusing Ground-Penetrating Radar Data. In Proceedings of the Third International Workshop on Advanced GPR, Delft, The Netherlands, 2005.
  49. O Lopera, B Macq, N Milisavljevic, and B Scheers. Denoising and migration techniques for landmine identification from Ground-Penetrating Radar 2D data. In eProceedings of GRETSI 2005, Louvain-la-neuve, Belgium, 2005.
  50. I. van den Bosch, P. Druyts, S. Lambot, I. Huynen, and M. Acheroy. Accurate and efficient modeling of monostatic GPR signal of dielectric targets embedded in stratified media. In Proceedings of the Progress in Electromagnetics Research Symposium (PIERS), pages 251-255, Hangzhou, Zhejiang, China, August 2005.
  51. I. van den Bosch, S. Lambot, M. Acheroy, I. Huynen, and P. Druyts. Accounting for multiple reflections and antenna radiation pattern in GPR signal modeling and experimental validation. In A. G. Gorriti S. Lambot, editor, Proceedings of the Third International Workshop on Advanced Ground-Penetrating Radar, pages 135-140, TU Delft, The Netherlands, May 2005.
  52. Pascal Druyts. Modeling a metal detector. In Y. Baudoin and P. Kopacek, editors, Proceedings of the International IARP Workshop on Robotics and Mechanical assistance in Humanitarian Demining and similar risky interventions, Royal Military Academy, Brussels, June 2004.
  53. O Lopera. Analysis and processing of two-dimensional data from ground-penetrating radar for Humanitarian Demining applications. Master thesis, 2004.
  54. O Lopera, S Lambot, I van den Bosch, A Gauthier, N Milisavljevic, and B Macq. A new signal processing approach for landmine signature extraction from Ground Penetrating Radar 2D data. In eProceedings of the IV National Congress on Automatization and Control, ISBN 958-8028-39-6, Bogota, Colombia, 2004.
  55. O Lopera, N Milisavljevic, B Macq, I van den Bosch, S Lambot, and A Gauthier. Analysis of segmentation techniques for landmine signature extraction from Ground Penetrating Radar 2D data. In eProceedings of the II International IEEE Andean Region Conference, ISBN 958-33-6534-3, Bogota, Colombia, 2004.
  56. O Lopera, I van den Bosch, S Lambot, N Milisavljevic, and B Macq. Simulation and analysis of ladnmine signatures from Ground Penetrating Radar 2D data. In Proceedings of the International Symposium Humanitarian Demining 2004, Sibenik, Croatia, 2004.
  57. S. Lambot, I van den Bosch, O Lopera, and E C Slob. Inverse identification of the shallow subsurface electric properties from frequency domain GPR signal for supporting humanitarian demining. In eProceedings of the II International IEEE Andean Region Conference, ISBN 958-33-6534-3, Bogota, Colombia, 2004.
  58. Pascal Druyts, Armin Merz, Markus Peichl, and Gunnar Triltzsch. HOPE : a hand-held multi-sensor (MD, GPR, MWR) mine detector prototype with imaging capabilities. In Proceedings of Progress in Electromagnetics Research Symposium (PIERS2003), Singapore, January 2003.
  59. S. Lambot, E. C. Slob, I. van den Bosch, B. Stockbroeckx, B. Scheers, and M. Vanclooster. GPR design and modeling for identifying the shallow subsurface dielectric properties. In Proceedings of the 2nd International Workshop on Advanced Ground Penetrating Radar, pages 130-135. Int. Res. Centre for Telecommunications-Transmission & Radar, 2003.
  60. P. Verlinde and A. Lewis. The joint multi-sensor mine-signatures project: an opportunity for testing data fusion algorithms!. In Proceedings of the Sixth International Conference of Information Fusion, pages 245-252, 2003.
  61. Pascal Druyts, Armin Merz, Markus Peichl, and Gunnar Triltzsch. HOPE : – raising the reliability of mine detection through an innovative a hand-held multi-sensor (MD, GPR, MWR) mine detector prototype with imaging capabilities. In Proceedings of the 3rd European-American Workshop on Reliability of NDE and Demining, Berlin, Germany, September 2002.
  62. P. Verlinde, M. Acheroy, G. Nesti, and A. Sieber. Preparing the Joint Multi-sensor Mine-signatures project database for data fusion. In IEEE International Geoscience and Remote Sensing Symposium, volume 7, pages 3240-3242. IEEE, 2001.
  63. Pascal Druyts, Lionel Merlat, and Marc Acheroy. Modeling considerations for imaging with a standard metal detector. In Abinash C. Dubey, James F. Harvey, J. Thomas Broach, and Regina E. Dugan, editors, Proceedings of SPIE Detection and Remediation Technologies for Mines and Minelike Targets V, volume 4038, pages 1431-1451, Orlando, FL, USA, August 2000.