Is all the tracing result only based on ADS-B signals received？
If so, have the ads-b ground receivers covered only united continent? or over the world?
at least in China, ads-b receivers only cover part airports, not all the airports and most lines？So, how do you count the location of the flights? based on radar? or something else?
Can anyone answer me this question?
ADS-B is not the only data source; FlightAware has dozens of other data feeds.
In addition to receiving over fifty different government air traffic control and private datalink sources, FlightAware operates a worldwide network of ADS-B receivers that track ADS-B-equipped aircraft flying around the globe. FlightAware owns and operates these receivers at dozens of airports around the world in conjunction with airport operators.
FlightAware currently provides private aviation flight tracking in over 45 countries across North America, Europe, and Oceania, as well as global solutions for aircraft with datalink (satellite/VHF) via every major provider, including ARINC, Garmin, Honeywell GDC, Satcom Direct, SITA, and UVdatalink. FlightAware also continues to lead the industry in free, worldwide airline flight tracking and airport status for air travelers.