AAIM uses additional on-board sensors to cross-check the GNSS position. The AAIM compares the 3D position with navigation information from on-board systems and not with signals from other satellites. The navigation systems on-board may be self-contained inertial reference system (IRS) or radio signals from navigation aids. Furthermore, redundancy to satellite signals may be offered by the barometric altimeter as a back-up for positioning in the vertical dimension.

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