With advances in sensor technology and the inclusion of low cost consumer grade sensors in portable systems like smart-phones, pedestrian navigation using such devices has become a reality. With consumer grade sensors comes a Pandora s Box full of errors rendering the unaided navigation solution with these sensors of limited use. A significant contribution to the overall navigation error budget associated with pedestrian navigation is accurate attitude estimation. This research develops different sensor fusion techniques to utilize the Earth s magnetic field for attitude and rate gyroscope...