Study on methods of sensitivity evaluation of JPM-4 proton magnetometer

Abstract

The filtering algorithm is usually applied to eliminate the diurnal variation in sensitivity estimation for proton magnetometer. Two indirect methods for sensitivity estimation of proton precession magnetometer, the synchronous measurement and the gradient measurement, are discussed here in detail. Experiments have been done under different electromagnetic environments and the sensitivity has been estiamted based on the two methods. Results show that both the indirect methods can suppress the interference of environmental noise effectively. The gradient measurement method is more accurate than synchronization measurement method. Finally, the sensitivity of JPM-4 proton magnetometer under 54000nT geomagnetic environment is estimated by the indirect methods as 0.1nT@3s.