By comparing the field and simulated data it was clear that the data did not agree with the simulation. Using Trimble Planning software an independent check was made and compared to the collected and simulated data. The satellite identifiers and visibility times were consistent with the data collected in the field and not with the simulated data. This suggested that there exists an error somewhere within the system of the program.

    The error mentioned was due to the surface model orientation with respect to the satellite constellation. However, the line of sight simulation code does function properly. With the correction of the surface orientation, the program would deliver accurate results. Samples of the simulation output can be downloaded by clicking on the picture (top-left).



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[4]        Intergovernmental Committee on Survey & Mapping (ICSM), Geocentric Datum of Australia Technical Manual V2.2, 2002.

[5]    J. DAWSON, J.STEED, International Terrestrial Reference Frame (ITRF) to GDA94 Coordinate Transformations, Geoscience Australia, 2004.

[6]        M. GERMROTH, L. CARTENSEN, GIS and Satellite Visibility: Viewsheds from Space, ESRI International User Conference, 2005.

[7]        YONG-CHEOL SUH, YUSUKE KONISHI, TOMOHIRO HAKAMATA, RYOSUKE SHIBASAKI, Development of a Simulation System for Assessing the Layout of Pseudolites in Urban Environment, Centre for Spatial Information Science, University of Tokyo, Japan. 

[8]        THE MATHSWORKS INC., Learning MATLAB 7 5th Ed., 2005.

[9]        MATLAB Help – Programming – Improving Performance and Memory Usage – Techniques for Improving Performance.


 Chaos Software Group Inc. (2006), World Time Server-Current Times, Viewed 20th September 2006, <>

 Satellite Navigation and Positioning Lab (2006), SNAP – Home, Viewed 9th October 2006, <>

MATHSWORKS (2006), Mathworks – Support, Viewed 27th August 2006, <>

Webpage created by Brendan O'Farrell, Last updated: 27/10/06, 18:00.