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Global Navigation Satellite Systems Report of a Joint Workshop of the National Academy of Engineering and the Chinese Academy of Engineering (2012) / Chapter Skim
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Application of GNSS to Environmental Studies--Penina Axelrad
Pages 179-188

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From page 179...
... Receivers measuring reflected signals are used to infer surface roughness and reflectivity, which can be related to surface conditions like ocean winds, soil moisture, and ice type. Modern receivers that can use multiple GNSS constellations will provide a rich global data set for environmental study.
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From page 180...
... Measuring reflected signals from ground, aircraft, or spacecraft enables retrieval of surface conditions including soil moisture, sea ice type, and ocean surface winds. ATMOSPHERIC SENSING Ground-based receivers at known locations measuring pseudorange and phase to all GNSS satellites in view provide useful observations for estimating precipitable water vapor (PWV)
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From page 181...
... It is notable that a National Research Council decadal survey in 2007 recommended that GPS-RO be made operational by NOAA and that additional GPS-RO instru ments be put on NASA science platforms whenever appropriate (NRC, 2007)
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From page 182...
... uses standard geodetic ground-based receiving equipment and models the effect of the surface reflections on the composite signal tracked by the receiver. The second approach, initially investigated by Martin-Neira (1993)
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From page 183...
... . Because this approach relies on standard geodetic receivers, the proliferation of such receivers for other geodetic purposes including earthquake monitoring, will make it possible to coincidentally observe Earth surface conditions with no additional expense or installations.
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From page 184...
... For this delay-mapping approach, a zenith antenna receives direct GPS signals, and a nadir antenna (with opposite polarization) receives the same GPS signals after reflection from surface below.
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From page 185...
... Courtesy of Stephan Esterhuizen. bitmap FIGURE 7 Model of effect of surface conditions on correlation function for reflected signals.
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From page 186...
... 2006. Remote Sensing of Ocean, Ice and Land Surfaces Using Bistatically Scattered GNSS Signals From Low Earth Orbit.
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From page 187...
... 2010. Sensing vegetation growth using reflected GPS signals.
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Key Terms

  • reflected signals
  • water vapor
  • gps signals
  • gnss signals
  • radio occultation

  • atmospheric water
  • surface conditions
  • surface sensing
  • initial results
  • moisture content

  • geophysical research
  • research letters
  • weather prediction
  • gps bistatic
  • gps multipath

  • gps tracking
  • gps radio
  • signals reflected
  • receivers measuring
  • atmospheric density

  • surface winds
  • precise orbit
  • composite signal
  • ice type
  • surface properties

  • bistatic radar
  • sensing relies
  • multiple gnss
  • standard geodetic
  • atmospheric sensing


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