Multi-Magnetometer Based Perturbation Mitigation for Indoor Orientation Estimation

Determining orientation with respect to a known reference plays an important role in almost all modes of navigation. As the sensors required for measuring magnetic field have found their way into portable navigation devices, researchers have started investigating their application to orientation estimation in different environments. Nevertheless, the success of these sensors for orientation estimation is conditioned by their capacity to sense Earth’s magnetic field in environments full of magnetic anomalies like urban canyons and indoors. These artificial fields contaminate Earth’s magnetic field measurements, making orientation estimation very difficult in heavily perturbed areas. To overcome the effect of magnetic anomalies, a perturbation mitigation technique is proposed that utilizes multiple magnetometers. This mitigation technique is then used for estimating Earth’s magnetic field indoors thus providing users with better magnetic orientation estimates. Performance of the proposed mitigation technique is assessed for pedestrian navigation in a shopping mall.