An innovative approach to 2D localization using the magnetic shielding effect

The effect on an electromagnetic field when a low-cost magnetically permeable object such as copper or aluminum is placed within it can be observed to determine the object’s location. This approach offers a novel technique to achieve reliable localization, particularly in environments where line of sight sensing methods may be non-applicable. Shields up to a size of 30×30 mm and a thickness of 80 µm were investigated; copper shields of these dimensions reduced the signal strength to 91 %, and aluminum shields reduced the signal strength to 94 % of its initial strength. The distortions to the electromagnetic field were closely related to the location of the tag. By fitting an inverted Gaussian curve to each sensor’s data, the position of a shield along a line could be predicted. This method can be used to locate a tag within a 2D plane by creating a 2D array of sensors beneath the sensing plane. • EMF shielding strength is dependent upon the position of the shield. • The intensity of shielding decreases with increased shield size and thickness. • Localized shielding of up to 8 % has been used to map the position of a shield.