Design Of Engineering Prototype For Digital Helium Optically Pumped Magnetometer

Digital helium optically pumped magnetometer is a helium atom energy level in the outside magnetic field generated in zeeman effect as the theoretical basis,through the optical pump function make the helium atom optical orientation,the method of using optical sensors detect magnetic resonance effect of measured magnetic field measurement,widely used in aviation magnetic survey,ground geophysical research,military defense,and other fields.Signal detection control circuit is the most key link helium optically pumped magnetometer,its track locking strategies adopted by the directly affect the instrument and the stability of the system.First in this paper,starting from the physical principle of optically pumped magnetometer helium,helium is studied the working principle of the optical pump magnetometer and fundamental wave signal of magnetic resonance curve and second harmonic signal amplitude characteristics are analyzed in detail,for helium optically pumped magnetometer for magnetic resonance point search strategy improvement method is proposedIn order to improve the stability and reliability of the system,this article uses the digital technology,under the processor based on FPGA design of helium optically pumped magnetometer detecting circuit,digital phase-locked amplifier is used to extract the signal,digital frequency modulation technology is used to produce frequency modulation.And join the second harmonic signal in the search strategy,using second harmonic signal amplitude characteristic of quick look resonance region,so as to speed up the tracking target resonance point.And use the RT-Thread operation system design human-computer interaction interface,the human-computer interaction interface is easy to use.Finally,the digital helium optically pumped magnetometer engineering prototype experiments,respectively set up by using ANSYS software and Pspice model on the structure and performance analysis was carried out on the circuit board,to verify the stability of the system reliability.