Magnetic navigation is a promising alternative for Autonomous Underwater Vehicles (AUVs), as they cannot rely on Global Navigation Satellite Systems underwater and commonly use Doppler Velocity Logs for navigation, whose acoustic emissions may be detectable during covert operations. One of the main challenges of magnetic navigation is the corruption of magnetic measurements by disturbances originating from the platform.

This thesis investigates whether map-less magnetic compensation using a magnetometer array is feasible for an AUV operating in regions with large magnetic anomalies, and whether reliable speed estimation can be achieved from the compensated magnetic measurements. The study evaluates the traditional aeromagnetic Tolles-Lawson (TL) compensation model and an extended model incorporating measurements from onboard electronics (OBE). A linear magnetic speed-estimation method was also investigated. The methods were evaluated using data collected as part of the Vinnova ENOK project during sea trials outside Askö in the summer of 2025. The dataset includes measurements from a three-sensor magnetometer array mounted on the AUV.

The results show that a significant portion of the platform-induced magnetic disturbances can be compensated and that the inclusion of OBE measurements further improves the compensation performance.  However, compensation remains challenging during certain diving maneuvers, likely due to changes in the platform's magnetic signature caused by thruster activation. No reliable speed estimates could be achieved using the compensated magnetometer measurements and the investigated linear speed-estimation method.