INERTIAL REFERENCE UNIT AND SYSTEM WITH ENHANCED INTEGRITY AND ASSOCIATED INTEGRITY-CHECKING METHODS

An inertial reference unit includes a first measurement channel comprising: a first high-performance inertial measurement unit comprising first measurement means for measuring specific forces and first measurement means for measuring angular velocities, a first computing unit able to compute pure inertial data based on the measurements of the first measurement unit; a second measurement channel comprising: a second inertial measurement unit of performance lower than the first inertial measurement unit, comprising second measurement means for measuring specific forces and second measurement means for measuring angular velocities; a second computing unit able to compute pure inertial data based on the measurements of the second measurement unit; an integrity check function able to implement a method for checking the integrity of the data of the first measurement channel based on the data provided by the second measurement channel; a synchronization means for synchronizing the measurements of the first and second inertial measurement units; the first and second inertial measurement units being mechanically mounted fixedly in the inertial reference unit.