Detection of DME ranging faults with INS coupling

In order to guarantee availability and continuity in Alternative Position Navigation and Timing (APNT), inertial systems are considered to coast the navigation position in case of navaids coverage gaps. For instance, DME/DME/Inertial (DDI) is currently considered for RNAV 1.0 operations. However, in order to support future RNP operations, the accuracy is not the only requirement to be fulfilled and other safety checks and integrity measures must be provided. This work analyses different fault detection mechanism for a multi-DME/Inertial system based on the innovation sequence of a Kalman filter. We aim to detect both single bias and ramp type fault profiles using snapshot and sequential test statistics. We evaluate the algorithms using our simulation framework based on real DME locations and realistic sensor error models.