Multiwire core fluxgate

Fluxgate sensors with core made of multiple microwires are analyzed. We show that any study on sensors based on microwires should begin with detailed characterization of the magnetic properties of the wire, as they are dramatically changing within centimeters. Increasing the number of wires increases the sensitivity and lowers the sensor noise; by proper grouping into serioparallel configuration the current and power consumption can be optimized. The achieved sensitivity is 30 mV/μT and noise level is 0.34 nT/√Hz@1 Hz for double-wire core with dipolar interaction.