Analysis of Spectrum Characteristics of GPS Time Comparison Under Two Conditions,

Abstract

In order to understand GPS time comparison characteristics associated with influences from SA (Selective Availability) effects, a number of experiments were carried out in early 1992. The data sampling time associated with the experiments was 10 seconds. Satellite tracking time was 1 hour. The results of frequency spectrum analysis clearly show that: (1) Under normal conditions, GPS time comparison spectrum characteristics are basically level. There are no clear periodic phenomena. Noise processes are phase modulated white noise. (2) When GPS time comparisons are influenced by SA effects, low frequency spectra are relatively clearer. There are obvious periodic phenomena. Among these, 5-15 minute period signals account for approximately 77%. This is nothing else than the cause which leads to obvious drops in GPS time comparison precision.

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Document Details

Document Type
Technical Report
Publication Date
Apr 01, 1996
Accession Number
ADA309965

Entities

People

  • Jinlun Hu
  • Shuguang Jian

Organizations

  • National Air and Space Intelligence Center

Tags

Communities of Interest

  • Space

DTIC Thesaurus Topics

  • Accuracy
  • Air Intelligence
  • Artificial Satellites
  • Autocorrelation
  • Dispersions
  • Frequency
  • Frequency Domain
  • Global Navigation Satellite Systems
  • Global Positioning Systems
  • Graphics
  • Noise
  • Power Spectra
  • Sampling
  • Spectra
  • Time Domain
  • Translations
  • White Noise

Readers

  • Control Systems Engineering.
  • Mathematics or Statistics
  • Positioning, Navigation, and Timing (PNT) Technology.

Technology Areas

  • Space