MSc research project

An autonomous magnetic field sensor is realized by integrating a thin film GMI sensor and SAW transponder. Single-electrode and double-electrode IDTs are employed, and the results show the latter design provides a superior performance in terms of sensitivity. Simulations based on the P-matrix model are carried out to optimize the matching between the transponder and sensor with respect to sensitivity. The combination of double-electrode IDTs with a three layer GMI sensor and optimum matching yielded a change of the reflection amplitude of 2.4 dB and a sensitivity of 0.34 dB/Oe. Future work will be directed at improving the performance of both SAW and GMI. The integrated sensor will be further miniaturized in order to realize a 433 MHz design. An antenna will also be integrated on board.

Full paper: Li, B.; Morsy, A. ; Kosel J., 2012, “Optimization of Autonomous Magnetic Field Sensor Consisting of Giant Magnetoimpedance Sensor & Surface Acoustic Wave Transducer”, IEEE Transactions on Magnetics 48 (11)