Analysis of NMR Signal for Static Magnetic Field Standard

Abstract

This article describes the analysis of the NMR (Nuclear Magnetic Resonance) stabilizer signal. Magnetic field of the standard is created using an electromagnet. Sufficiently high stability of the magnetic field is achieved with the help of a stabilizer with an NMR probe. The NMR phenomenon makes possible very accurate measurements of the static magnetic field, but the resulting stability depends also on supporting electronics. An analysis has been done and tolerances of the measured quantities have been estimated. The calculated tolerances indicate the needed features of the material. First the probe excites the FID (Free Induction Decay) signal in the water sample and acquires the signal answer. It is Fourier transformed and its spectrum is investigated. The actual magnetic field corresponds to the strongest frequency sample. It is utilized for the magnetic field strength correction and stabilization of it. The article brings many equations for such calculation.