Single-board low-noise fluxgate magnetometer

Abstract

Low-noise fluxgate magnetometers are normally comprised of three separate devices: a power supply, the sensor head/electronics and an analog-to-digital converter (ADC). This paper presents a parallel rod fluxgate magnetometer in a single printed circuit board of size=5×12 cm, weight=45 g, and sensor head average power dissipation = 40 mW. The open-loop noise spectral density =5pTrms/Hz@1Hz, competitive with state-of-the-art devices. This is realized using a new amorphous wire core material and programmable mixed-signal electronics with low amplifier and ADC noise. We have compared the sensor performance to a low-noise observatory magnetometer and found sub-nT correlation when tracking the Y (East-West) component of the Earth’s geomagnetic field.