It’s Just ADS-B
Aireon’s space-based global surveillance system is just Automatic Dependent Surveillance-Broadcast (ADS-B) on a satellite. Instead of utilizing traditional radio receiver towers on the ground, Aireon has redesigned them into flexible and highly effective space-grade receivers on Iridium’s second generation satellite constellation, Iridium NEXT. This will allow for 100 percent global surveillance using the same ADS-B signal that aircraft already transmit.
What is ADS-B?
ADS-B is a surveillance technique that relies on aircraft broadcasting their identity, a precise GPS position and other information derived from on-board systems. ADS-B is automatic because no work is required from the pilot or Air Traffic Controller (ATC). It is also dependent because it relies on on-board avionics to provide surveillance information to other parties. The data is broadcast every half a second from the aircraft and can be received without a contract.
ADS-B is seen as a key enabler of advanced global surveillance. It is cheaper than traditional radar infrastructure while providing a more frequent and accurate position to the controller, including enhanced data fields.
A key benefit of Aireon’s ADS-B data is that it can also be used for post-flight analysis and allow a live data feed to other aviation systems for enhanced resource planning and operational decision making.
- Automatic: periodically transmits information with no pilot or operator input required
- Dependent: position and velocity vector are derived from the Global Positioning System (GPS)
- Surveillance: a method of determining position of aircraft, vehicles or other asset
- Broadcast: transmitted information available to anyone with the appropriate receiving equipment
For more technical information, see Figure 1 below:
|ATS Surveillance Requirements (EUROCAE)||Aireon|
|Surveillance Data-link Requirements||Variable Per Region|
(DO-260 Version 0, 1, 2)
|Accepts all 1090ES ADS-B (DO-260 Versions 0, 1, 2)|
|Aircraft Transmitter Classes Supported||A1 or Higher (125 Watt minimum)||A1 or Higher (125 Watt minimum, with a top-mount antenna (TCAS)|
|Data Format to ANSP||ASTERIX CAT021, CAT023, CAT025 and FAA CAT033 and CAT023||ASTERIX CAT021, CAT023, CAT025 and FAA CAT033 and CAT023|
|System Coverage||En Route Service Volume (200 NM)||Continuous Global Coverage|
|Availability||≥ 99.9%||≥ 99.9%|
|Latency||≤ 1.5s to the ATM Automation Platform||≤ 1.5s to the ATM Automation Platform|
|Update Interval||≤ 8s at 95%|| Simulation and testing shows that targets will be delivered at an
UI of ≤ 8s* at 95%