NISCAIR Online Periodicals Repository

NISCAIR ONLINE PERIODICALS REPOSITORY (NOPR)  >
NISCAIR PUBLICATIONS >
Research Journals >
Indian Journal of Radio & Space Physics (IJRSP) >
IJRSP Vol.36 [2007] >
IJRSP Vol.36(5) [October 2007] >


Title: Ionospheric studies for the implementation of GAGAN
Authors: Acharya, Rajat
Nagori, Neha
Jain, Nishkam
Sunda, Surendra
Regar, Sawarmal
Sivaraman, M R
Bandopadhyay, Kalyan
Keywords: GPS
Equatorial ionosphere
SBAS
GAGAN
Ionospheric Large scale model
Kriging
scintillation
Issue Date: Oct-2007
Publisher: CSIR
Abstract: Satellite Based Augmentation System (SBAS), being developed by Indian Space Research Organization (ISRO) in collaboration with Airports Authority of India (AAI) is known as “GPS Aided GEO Augmented Navigation” (GAGAN). It is expected to offer better accuracy and integrity of navigation service than with GPS alone by providing correction terms to the GPS signals. This is achieved by modelling a Near Real Time Grid Based Ionospheric Delay Model for correcting propagation delay at 1575.42 MHz (L1) using measurements at 1575.42 and 1227.6 MHz (L2). Existing algorithms are replaced by Kriging based model to meet the requirement of correction with 0.5 m maximum residue over Indian region. Details of the data collection and pre-processing, including estimation of the Total Electron Content (TEC), which is a measure of ionospheric delay, has been described. Kriging algorithm and some preliminary results of studies are also presented in this paper. This includes the spatial decorrelation of the stochastic random field over the deterministic variation of ionospheric TEC. Its variation with time and locations are investigated and a temporal dependence found to exist. Large scale ionospheric irregularities and depletions that cause severe amplitude and phase scintillations are also studied. Their impacts on GAGAN are also shown. Some major scientific studies required to be carried out over Indian region to improve the GAGAN performance is discussed.
Page(s): 394-404
ISSN: 0367-8393
Source:IJRSP Vol.36(5) [October 2007]

Files in This Item:

File Description SizeFormat
IJRSP 36(5) 394-404.pdf518.96 kBAdobe PDFView/Open
 Current Page Visits: 793 
Recommend this item

 

National Knowledge Resources Consortium |  NISCAIR Website |  Contact us |  Feedback

Disclaimer: NISCAIR assumes no responsibility for the statements and opinions advanced by contributors. The editorial staff in its work of examining papers received for publication is helped, in an honorary capacity, by many distinguished engineers and scientists.

CC License Except where otherwise noted, the Articles on this site are licensed under Creative Commons License: CC Attribution-Noncommercial-No Derivative Works 2.5 India

Copyright © 2012 The Council of Scientific and Industrial Research, New Delhi. All rights reserved.

Powered by DSpace Copyright © 2002-2007 MIT and Hewlett-Packard | Compliant to OAI-PMH V 2.0

Home Page Total Visits: 603726 since 06-Feb-2009  Last updated on 21-Oct-2014Webmaster: nopr@niscair.res.in