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Other Regional Systems

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Other RegionalOther Regional
Title Other Regional Systems
Author(s) GMV.
Level Basic
Year of Publication 2011
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There are nowadays three regional navigation satellites systems under development: the japanase QZSS, the indian IRNSS and the chinese BeiDou. The first two are explained in dedicated articles and BeiDou system is going to be explained next.

BeiDou-1

BeiDou-1 is the chinese experimental regional navigation system. In 1994, the Chinese government authorized to start the development and deployment of an experimental satellite navigation system based on the twin-satellite navigation system. The two GEO satellites, Beidou 1A and Beidou 1B, were launched in 2000. The system began to provide positioning service in late 2001. In May 2003, the successful launch of BeiDou-1C also meant the establishment of the BeiDou-1 system. The BeiDou-1 service is available to civilian users since 2004.[1] and the system services and performance characteristics at this time (2004) were:[2]

  • Positioning: 100m (1σ); 20m (1σ, with reference stations).
  • Regional Service short message service (SMS): up to 120 Chinese characters.
  • Timing: 20 ns.

BeiDou-2

The initial phase of the COMPASS/BeiDou-2 global navigation system is the implementation a chinese regional system, with much higher accuracy to replace BeiDou-1. By April 2011, this initial phase of COMPASS system has been completed with a constellation of 4 GEO satellites and 3 IGSO satellites. During 2011, the system is going to launch another 4 BeiDou Navigation Satellites, providing initial passive positioning navigation and timing services for the whole Asia-Pacific region, this will complete the BeiDou-2 regional system by 2012.[3]

The list of BeiDou-2 satellites can be found in article COMPASS Space Segment. During 2011, the system is going to launch another 4 Beidou Navigation Satellites, providing for the whole Asia-Pacific region:[3]

- initial passive positioning navigation;

- timing service;

- and short message communication (120 Chinese characters per message) service.

The aim of the regional BeiDou system (completion expected by end of 2012) is to provide two types of services:[3]

  • Open service: a free service for civilian users with positioning accuracy of within 10 metres, velocity accuracy of within 0.2 m/s and timing accuracy of within 20 nanoseconds;
  • Authorized service:a licensed service with higher accuracy even in complex situations for authorised and military users only.

These services are available for the BeiDou coverage area, i.e. China and its neighbouring countries.

Notes


References

  1. ^ Compass Satellite Navigation System (Beidou), on Sinodefence.com, updated on August 6th, 2011.
  2. ^ Compass/BeiuDou status presentation in Rome (Italy), June 11, 2009.
  3. ^ a b c COMPASS Status Presentation, Munich Satellite Navigation Summit March 2011.