Studies of an Optimally Unbiased MA Filter Intended for GPS-Based Timekeeping

Abstract

In this paper, we examine one of the possible approaches to design an optimally unbiased moving average (MA) filter intended for the time error online estimating and synchronization in timekeeping. The approach is based on the slowly changing nature of a time error generated by the local clock and has led to a simple formula for the optimally unbiased MA filter, which does not require any a priori knowledge about the time error process. When filtering the various GPS-based time error processes, we found out that, of the filters with the same time constant, the designed filter demonstrates an error intermediate between the three-state and two-state Kalman filters. The filter has been examined for numerically simulated data and some practical situations of the GPS-based time errors generated with the crystal and rubidium oscillators.

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Document Details

Document Type
Technical Report
Publication Date
Nov 01, 2001
Accession Number
ADA485635

Entities

People

  • O. Ibarra-manzano
  • R. Rojas-laguana
  • R. Vazguez-bautista
  • Y. Shmaliy

Organizations

  • Universidad de Guanajuato

Tags

Communities of Interest

  • Materials and Manufacturing Processes
  • Space

DTIC Thesaurus Topics

  • Algorithms
  • Clocks
  • Computational Complexity
  • Crystal Oscillators
  • Errors
  • Filters
  • Filtration
  • Frequency
  • Global Positioning Systems
  • Intervals
  • Kalman Filtering
  • Kalman Filters
  • Noise
  • Random Walk
  • Simulations
  • Time Intervals
  • Weighting Functions

Readers

  • Electrical Engineering
  • Positioning, Navigation, and Timing (PNT) Technology.
  • Statistical inference.

Technology Areas

  • Space