PRECISE REALTIME DIFFERENTIAL NAVIGATION USING NTRIP STREAMS FROM CONTINUOUSLY OPERATING, WIDEAREA G

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PRECISE REAL-TIME DIFFERENTIAL NAVIGATION USING
NTRIP STREAMS FROM CONTINUOUSLY OPERATING,
WIDE-AREA GNSS NETWORKS.

• Oscar L. Colombo
• GEST/NASA Goddard Space Flight Center Maryland,
  USA

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COMMENTS

• NTRIP data freely available from GNSS networks
  provide an invaluable test-bed for innovation.
• SBAS networks now begin operations, or are under
  development, in several countries, including
  developing ones, while more plan to build their
  own in the future.
• Wide-area precise real-time kinematic positioning
  (with floated ambiguities) typically needs a
  long time (30min 1.5 hs) assimilating data
  before the solution converges to its full
  precision.
• New signals (L2C, L5, P5) can help shorten the
  convergence time, but their transmitter code
  biases have to be corrected using estimated
  values. Also the non-integer part of
  un-differenced L1, L2 ambiguities could be
  calibrated with data from the world-wide IGS
  network, to assist wide-area point-positioning.
• The IGS (or some IGS ACs) could help by
  providing some, or all, of the corrections
  mentioned above, much as CODE does now with the
  P1-C1 biases.

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NTRIP Sites, Many Available through BKG(Mostly 1
Hz GPS data, Raw or RTCM 2.x, 3.0)
Map BKG, Frankfurt
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Some countries are developing or considering
SBAS, DGPS, Precise DGPS. More could soon join
them.
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Source BKG, Frankfurt
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USA Off-Line Test, April 2004
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The IT Real-time navigation software has been
developed with support from the US Navy
(NSWC-Dahlgren Division)
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Spanish Sites Test, 25 February 2008
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Iberian Test Sites, April 28, 2008
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A WORD OF CAUTIONFirst Sunspot of Cycle 24
Already Sighted
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Near Solar Max., Ionospheric Scintillation can be
a serious problem at low latitudes (Tropical
Anomaly)
Prof. Claudio Brunini, UNLP