A new control method to generate RF signal for a novel NMR magnetometer

The main purpose of nuclear magnetic resonance (NMR) magnetometer is to calibrate the magnetic field. The core of the traditional NMR magnetometer is marginal oscillator, but the precision of marginal oscillator is not high enough. The paper chiefly presents a new control method to generate RF signal for a novel NMR magnetometer. The basic structure and operation principle of the novel NMR magnetometer is simply described here. In order to improve the precision of NMR magnetometer, the RF signal is generated by the Direct Digital Synthesizer (DDS) technology and the Phase Locked Loop (PLL) technology instead of the marginal oscillator. The circuit system of generating RF is designed and developed. The working performance is tested. Its precision is approximately 0.1ppm. The experimental result shows that this control method is feasible and the NMR signal can be detected clearly.