Improvement of Link 16 Navigation Via Real-Time Atmospheric Modeling

Abstract

This study examines an algorithm, called the Atmospheric Filter, which improves upon the current method employed in the Unk-16 MIDS terminal to compensate for the effects of atmospheric refraction on the range estimation to a Unk- 16 emitter. It is implemented in the form of a Kalman Filter to estimate the parameters of the refractivity modeled as an exponentially decaying function of altitude above sea level. The refractivity is used to correct the time a signal takes to travel from the emitter to the receiver. This then is used to estimate the range to the emitter. A truth model is used in this study to create realistic pseudo-measurements of the true range in order to determine the range errors due to the AF refractivity corrections. The goal is to reduce these errors by an order of magnitude and thus improve the performance of the existing navigation algorithms. It is shown in this report that this simple exponential model agrees well with the well known, much more elaborate models of tropospheric refractivity. These models require large amounts of detailed meteorological data using up considerable computing resources, both in data storage and also processing.

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Document Details

Document Type
Technical Report
Publication Date
Sep 30, 2003
Accession Number
ADA419378

Entities

People

  • Joel D. Reiss
  • Ralph R. Demarco

Tags

Communities of Interest

  • Biomedical
  • Materials and Manufacturing Processes
  • Sensors
  • Space
  • Weapons Technologies

DTIC Thesaurus Topics

  • Algorithms
  • Altitude
  • Computer Programs
  • Computers
  • Data Storage Systems
  • Earth Models
  • Geometry
  • Grids
  • Inertial Navigation
  • Kalman Filters
  • Measurement
  • Meteorological Data
  • Navigation
  • Procedures (Computers)
  • Refractive Index
  • Sea Level
  • World Geodetic System

Readers

  • Adaptive Control and Estimation with Uncertainty in Dynamic Systems.
  • Ocean-Atmosphere Mesoscale Modeling, Data Assimilation, and Flux Boundary Layers
  • Positioning, Navigation, and Timing (PNT) Technology.