Fluxgate gradiometer

U ovom Završnom radu je objašnjena teorijska podloga i načelo rada Fluxgate magnetometara i gradiometara te su opisane neke od njihovih primjena. Istaknute su prednosti Fluxgate magnetometara te su uspoređena svojstva različitih izvedbi. Provedena je analiza postojeće izvedbe te je utvrđeno kako postoji značajna asimetrija između sondi i napon pomaka. Bitno je istaknuti važnost smanjenja napona pomaka i otklanjanja asimetrije jer je uređaj namijenjen za mjerenje bioloških magnetskih polja gdje je potrebna visoka osjetljivost. Asimetrija je otklonjena izradom novog para sondi Fluxgate gradiometra i prilagodbom ulazne impedancije. Napon pomaka je smanjen spajanjem promjenjivih otpornika na predviđena mjesta i ugađanjem te pravilnim razvođenjem mase. Sve izmjene na uređaju su detaljno opisane i izneseni su razlozi za njihovu provedbu te je prokomentiran učinak svake od izmjena na rad cijelog uređaja. Na kraju rada je iznesen prijedlog nove izvedbe Fluxgate gradiometra koja bi se mogla primijeniti u magnetokardiografiji i magnetomiografiji. In this BSc Thesis theoretical background and operating principle of Fluxgate magnetometer and gradiometer are explained. Some applications of Fluxgate gradiometer and magnetometer are described. The advantages of Fluxgate gradiometer are described and performances of different implementations are compared. Existing prototype was analyzed and there was found significant asymmetry between two probes and offset voltage. It is important to reduce offset voltage and eliminate asymmetry because device is intended to measure biological magnetic fields (high sensitivity is required). Asymmetry was eliminated by developing a new pair of Fluxgate gradiometer probes and adapting input impedance. The offset voltage was reduced by connecting trimmer resistors and properly connecting ground wires. Every modification on the device is described in detail and the reasons for their implementation are explained. New implementation of Fluxgate gradiometer which could be applied in magnetocardiography and magnetomyography is suggested at the end of the assignment.