Wirelessly interrogable magnetic field sensor utilizing giant magneto-impedance effect and surface acoustic wave devices

Integration of thin film giant magnetoimpedance sensor and surface acoustic wave transponder

“…7 The sensitivity (16%/Oe) is in the same range of the GMI wire sensor (100-1200%/mT), which was used previously to integrate with the SAW device. 21 In case of the thin film sensor, the magnetic field region of high sensitivity is lower compared to …”

“…With regard to two-port magnetic SAW sensors, one concept was presented previously utilizing a GMI wire and a SAW transponder. 21,22 In this work, an integrated device consisting of a trilayer thin film GMI sensor and a SAW transponder is designed, fabricated, and measured. This integrated device is proposed for passive and remote magnetic sensing applications such as implantable devices or harsh environments, while offering the advantages of mass fabrication.…”

Surface Acoustic Wave Based Magnetic Sensors

“…The resonant frequency of the device changes with an external magnetic field. A different idea was put forth by Hauser and Steindl [14][15][16] combining a SAW transducer with a giant magnetoimpedance (GMI) microwire sensor. The GMI sensor has a magnetic sensitivity, at least, one order higher than contemporary giant magnetoresistance (GMR) sensors and can be used to measure very low magnetic fields such as those generated by the human heart or muscles.…”

“…In the first studies, SAW transponders and GMI wire sensors were combined to form remote devices [14][15][16]. GMI wires were selected for their high sensitivity, and they were bonded to the output IDT of the SAW device, which operated as a reflector, in order to act as load impedance.…”

Transdutor De Pressão Ultrassensível Baseado Na Leitura De Fase De Sensores Gmi

“…Apesar de ter sido observada em 1935 [1], só atraiu a atenção dos pesquisadores na década de 1990, quando passaram a enxergar seu grande potencial [11][12]. Mesmo encontrando-se ainda em fase de desenvolvimento, já foi usada para diversas aplicações, dentre as quais se podem destacar: detectores de presença [26], controle de processos industriais [27], pesquisa espacial e aplicações aeroespaciais [11][12][13][14], sistemas de navegação [18], memórias de alta densidade e HDs [28], controle de tráfego [15], detecção de fissuras em materiais [16][17], microfluídica [29] e aplicações biológicas e biomédicas [3,[19][20].…”