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Volume 61 Supplement 5

Special Issue: Flare-Substorm/Space Weather Topics

Investigation of ionospheric gradients for GAGAN application

Earth, Planets and Space volume 61, pages 633–635 (2009)Cite this article

Abstract

To cater to the needs of aviation applications, GPS Aided GEO Augmented Navigation (GAGAN) system is being implemented over the Indian region. The most prominent parameter affecting the navigation accuracy of GAGAN is ionospheric delay which is a function of TEC. In the equatorial and low latitude regions such as India, TEC is often quite high with large spatial gradients. Carrier phase data from the GAGAN network of Indian TEC Stations is used for estimating ionospheric gradients in multiple viewing directions. Rate of TEC (ROT) and Rate of TEC Index (ROTI) are calculated to identify the ionospheric gradients. Among the satellite signals arriving in multiple directions, the signals which suffer from severe ionospheric gradients are identified and avoided for improving GAGAN positional accuracy. The outcome of this paper will be helpful for improving GAGAN system performance.

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Authors and Affiliations

  1. Research and Training Unit for Navigational Electronics, Osmania University, Hyderabad, India

    K. Ravi Chandra, V. Satya Srinivas & A. D. Sarma

Authors
  1. K. Ravi Chandra
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  2. V. Satya Srinivas
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  3. A. D. Sarma
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Corresponding author

Correspondence to A. D. Sarma.

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Chandra, K.R., Srinivas, V.S. & Sarma, A.D. Investigation of ionospheric gradients for GAGAN application. Earth Planet Sp 61, 633–635 (2009). https://doi.org/10.1186/BF03352939

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  • DOI: https://doi.org/10.1186/BF03352939

Key words

  • GAGAN
  • ionospheric gradients
  • ROT
  • ROTI