The Time Keeping System for GPS Block IIR

Abstract

The precision time keeping system (TKS) in the Global Positioning System (GPS), Block IIR satellites is designed to operate under severe natural and man made environmental conditions. The Block IIR TKS provides precise, autonomous time keeping for periods of up to seven months, without the intervention of the GPS Control Segment. The TKS is implemented using both linear and non-linear controls. The resulting TKS architecture uses a hybrid analog/digital phase locked loop (PLL). The paper provides details of the design and analysis of the TKS. The simulation techniques and the test bed activities used in performing the TKS design trade-offs are described. The effects of non-linear controls are analyzed using a TKS computer simulation of the PLL. The results from a hardware test bed are provided that verify desired TKS operation. The design criteria for the TKS computer simulation and the hardware test bed are indicated. The concepts for verification and testing of the TKS computer simulation and hardware test bed are presented.

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Document Details

Document Type
Technical Report
Publication Date
Dec 01, 1992
Accession Number
ADA518814

Entities

People

  • H. C. Rawicz
  • J. A. Rajan
  • M. A. Epstein

Tags

DTIC Thesaurus Topics

  • Accuracy
  • Algorithms
  • Artificial Satellites
  • Bandwidth
  • Clocks
  • Computer Simulations
  • Computers
  • Frequency
  • Generators
  • Global Positioning Systems
  • Navigation
  • Noise Generators
  • Phase Meters
  • Simulations
  • Steady State
  • Test Beds
  • Time Intervals

Readers

  • Computational Modeling and Simulation
  • Positioning, Navigation, and Timing (PNT) Technology.
  • Software Engineering

Technology Areas

  • Space
  • Space - Spacecraft Maneuvers