Method and apparatus for improving ADS-B security
Security of ADS-B transmissions is improved in a first embodiment to detect position spoofing. The annunciated position source may then be compared with the derived source and a determination is made regarding the difference between the results. Any position difference greater than an amount significantly greater than the combination of the error sources is then a cause for concern and can be used to generate an alert. In a second embodiment, alerting may be based on identification spoofing. From these sources a correlated ID is available which will have an associated confidence based on the number of sources and the level of agreement on the information. Aircraft dynamics may be correlated with the announced ID for consistency. A priori information on the aircraft and location, such as schedule information, and normal operations, may be used to assist in the confidence of aircraft identity. In a third embodiment, alerting may be based on spoofing of identity and position.
1. A system for authenticating position signals of an aircraft, comprising:
a first input for receiving an annunciated aircraft position from at least one aircraft generated source, the annunciated aircraft position indicating an annunciated position of the aircraft,
a second input for receiving a derived aircraft position from a non-aircraft generated source, indicating position of the aircraft,
a comparator, for comparing the annunciated aircraft position with the derived aircraft position and generating an alarm if the annunciated aircraft position is not within a predetermined range of the derived aircraft position.
2. The system of claim 1 , wherein the aircraft generated source includes one or more of ADS-B such as the Universal Access Transceiver (UAT), VHF Data Link (VDL), and 1090 MHz ADS-B.
3. The system of claim 1 , wherein the non-aircraft generated source includes one or more of a multilateration system, primary and Secondary Surveillance Radar (SSR), conventional rotating radar, and passive radar.
4. The system of claim 1 , wherein annunciated positions may be correlated through a Traffic Information Service Broadcast (TIS-B) system.
5. The system of claim 1 , wherein the predetermined range is derived from a combination of the error sources for the annunciated position source and the derived position sources.
6. The system of claim 3 , wherein the multilateration system includes a plurality of antennas, at least some of which are mounted to cellular phone towers.
7. A system for authenticating aircraft identification signals of an aircraft, comprising:
a first input for receiving an annunciated aircraft identification from at least one aircraft generated source, indicating identification of at least one of aircraft type, aircraft identification, flight identification, and aircraft performance, for the aircraft,
a second input for receiving a derived aircraft identification from a non-aircraft generated source, indicating identification of at least one of aircraft type, aircraft identification, flight identification, and aircraft performance,
a comparator, for comparing the annunciated aircraft identification with the derived aircraft identification and generating an alarm if the annunciated aircraft identification is not within a predetermined range of the derived aircraft identification.
8. The system of claim 7 , wherein the aircraft generated source includes one or more of ADS-B such as the Universal Access Transceiver (UAT), VHF Data Link (VDL), and 1090 MHz ADS-B.
9. The system of claim 7 , wherein the non-aircraft generated source includes one or more of a multilateration system, primary and Secondary Surveillance Radar (SSR), conventional rotating radar, and passive radar.
10. The system of claim 7 , wherein annunciated identifications may be correlated through a Traffic Information Service Broadcast (TIS-B) system.
11. The system of claim 7 , wherein aircraft performance comprises dynamics of the aircraft, which include one or more of minimum and maximum velocities, flight levels, and vertical descent/ascent rates.
12. The system of claim 7 , wherein flight identification includes schedule information.
13. The system of claim 9 , wherein the multilateration system includes a plurality of antennas, at least some of which are mounted to cellular phone towers.