WAAS Network Time Performance Using WRS Data

Abstract

Raytheon Systems Company is currently designing the algorithms of the FAA's Wide Area Augmentation System (WAAS). This paper will briefly overview the WAAS network time (WNT) algorithms and their integration into the overall system. The WAAS system is required to provide users with orbit, clock, and ionosphere corrections for single-frequency measurements of the GPS signal. The clock corrections will be made in the WAAS network time (WNT) reference scale. This reference scale is required to track the GPS time scale, while at the same time providing the users with the translation to UTC. This design must provide the user a seamless transition when switching from one WMSs WNT realization to another. This paper expands on two previous papers, one presented at ION GPS-97 using simulated clock data as input, and the other presented at the I999 Technical Meeting using receiver data from the National Satellite Testbed (NSTB) and preliminary WAAS data. We included some introductory sections from previous papers here for completeness. Here, we will present the performance results of the WNT algorithm using GPS clock and receiver data from WAAS Reference Station (WRS) using the standalone WNT algorithm with the WAAS prototype software. We will also show some recent WNT algorithm results from the operational WAAS software, indicating that the WNT design should meet the aforementioned requirements, taking into account possible WAAS WMS switches.

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Document Details

Document Type
Technical Report
Publication Date
Dec 01, 1999
Accession Number
ADA495605

Entities

People

  • Cheryl Griffith
  • Peter Diamond
  • Stephen Peck

Organizations

  • RTX

Tags

DTIC Thesaurus Topics

  • Accuracy
  • Algorithms
  • Artificial Satellites
  • Clocks
  • Computations
  • Data Sets
  • Filters
  • Frequency
  • Kalman Filters
  • Measurement
  • Nanosecond Time
  • Navigation
  • Orbits
  • Spacecraft
  • Standards
  • Time Intervals
  • Time Standards

Fields of Study

  • Computer science

Readers

  • Database Systems and Applications
  • Positioning, Navigation, and Timing (PNT) Technology.

Technology Areas

  • Space