“…This basic phenomenon was first reported long time ago in the 1930s [5], but without attracting so much noticeably for applications. The re-discovering of MI effect has overcome huge efforts from then up to nowadays, in order to find the more appropriated magnetic materials and treatments for using them as sensitive elements in sensor devices with high MI responses [6][7][8]. Descriptions of different MI-based field sensor prototypes are widely available in the literature together with their advantages, disadvantages and comparative analysis of MI sensors with other types of magnetic detectors [3,[8][9][10][11].…”