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Compass system accuracy and results 2012





  • compass on the road to global positioning system
  • compass( current 5+5+4 constellation and regional tracking system) Tgd: 2 ~ 30 ns.with variation modelled and predicted to be better than 1.0 ns
  • Compass Ionosphere model shows better performance than GPS model for single frequency receivers
  • Better than 10m accuracy for dual frequency civilian users, 2m for authorized users
  • Better than 5 cm for post-processing positioning using daily phase data

From Shanghai Astronomical Observatory ( SHAO) Jan 2012

According to Xinhua news agency reports, Ran said Beidou’s general functionality and performance within China was “comparable” to the GPS system, with stand-alone positioning accuracy of 10 meters, velocity accuracy of 0.2 meters per second, and one-way timing accuracy of 50 nanoseconds.

In the lower graphs, presenting the I/Q constellation diagrams, the authors point out an obvious improvement of the modulation quality over time and generations, especially of the latest middle Earth orbiting M5 satellite compared to the first M1 satellite. “The IGSO-1 and the M5 are more or less nearly perfect,” they wrote.
As BeiDou’s system managers and political overseers absorb the program’s accomplishments, they may preserve the nominal 2020 date for completing a full global system. The final constellation will be made up of 5 GEOs, 3 IGSOs, and 27 MEOs — a total of 35 satellites, which would make it the largest of the four GNSS systems.

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