Improving Magnetic Flux Density Fingerprint Map Matching by Mitigating AC-Induced Variability

Magnetic flux density (MFD) map matching is a technique that can provide absolute position solutions by comparing a series of MFD measurements with a database. Map matching relies on the consistent measurement of the same physical phenomena during the surveying and positioning phases. However, fluctuations in MFD due to alternating current (AC) electricity, influenced by dynamic power requirements, pose a challenge. This paper analyses the characteristics of the influences of AC sources on MFD measurements. It shows that employing spectral filtering can isolate magnetic perturbations from AC sources, which could be used to enhance the magnetic map matching’s resilience to this form of temporal change.