Joint Positioning and Time Synchronization for Alternate Positioning, Navigation and Timing (APNT)

Kurzfassung

The paper presents a concept to perform a position and time solution by an Alternate Position, Navigation and Time (APNT) system. It is know that one-way range measurements provided by the APNT system are affected by the time errors of the involved station and aircraft clocks. The presented concept does not require an additional time signal to synchronize the system. The mitigation is yielded by processing a window of pseudo range measurements and by assuming the involved clock solutions to be fixed over the window. The details of the joint position and time synchronization method are described in the paper. In particular its impact on the horizontal position error is simulated for different APNT scenarios derived from a measurement campaign. The results show that errors beyond the 20 meter level can be reached by the on-board aircraft concept for APNT systems.