Single-antenna global positioning system (GPS)-based attitude determination method is simple and cost-effective because it make possible to use a GPS receiver as a sole sensor for aircraft navigation system. Its usefulness as backup system for inertial sensor-based navigation system and main navigation system for low-cost unmanned aerial vehicle (UAV) has proven. However, even now this method is not correspond to rapid maneuver of the aircraft because the pseudo-attitude, which is attitude comes from this method has low-rated output, time lag and deviation from true attitude. To overcome the shortcomings of pseudo-attitude, integration with gyroscope and magnetometer was proposed. The proposed method showed improved accuracy and stability of the estimated attitude. In this method, the magnetometer contribute to estimate true pitch and yaw angle. Moreover, it can provide the attitude information even if GPS is not available. In this paper, the single-antenna GPS-based attitude determination method integrated with gyroscope and magnetometer is tested under GPS outage. The results shows that attitude information from magnetometer prevents the estimated attitude from divergence for a while under GPS outage condition. Therefore, this method can deal with short GPS outage and enhances the viability of UAV for GPS outage situation.

Keywords: global positioning system (GPS), gyroscope, magnetometer, attitude