Avionics can use satellite-based systems (GNSS), ground-based systems (such as ILS and VOR), or any combination thereof. New capabilities will include improvements in navigation to extend performance-based time requirements throughout the aircraft’s planned trajectory and integration of a two-way data link capability with the navigation systems to request and update 4D trajectory clearances.
Airborne technological changes are also drawing navigation closer together with communications and surveillance. Nowadays, pilots can monitor navigation data (flight planned route) with superimposed Airborne Collision Avoidance System (ACAS) data on one Electronic Flight Instrument System (EFIS) display and toggle between radio communication channels and navigation function selections on a single control device.
In terms of navigation, the following avionics-related systems can be considered:
Area navigation systems (RNAV) that uses a method of navigation which permits aircraft operation on any desired flight path within the coverage of referenced navigation aids or within the limits of the capability of self-contained aids, or a combination of these (en-route, terminal and approach navigation)
Navigation sensors that enable aircraft to determine either the correct path to a known point, or their current position, velocity and time (PVT) in order to be used by a navigation computer to calculate the required path to any point. Some civil aircraft also make use of Inertial Navigation Systems (INS) which can be very accurate over short distances but drift with time. It is likely that INS will be more closely integrated into the PVT solution and hence improve the overall integrity of the positioning data.
Landing systems that will provide aircraft with a precision approach capability. There are three principle Precision Approach landing systems: ILS (Instrument Landing System), MLS (Microwave landing System) and GLS (GNSS - Global Navigation Satellite System) Landing System. All three systems may be implemented in a Multi-Mode Receiver (MMR) on board the aircraft.