10.4225/03/59f257836e421 M. Sreedhar M. Sreedhar B. Narender B. Narender S. Muralikrishnan S. Muralikrishnan Line of sight analysis for urban mobile applications: a photogrammetric approach Monash University 2017 Cartosat-1 Geoeye-1 DSM Line of sight GAGAN IRNSS mobile applications Geography Geospatial Information Systems 2017-10-26 21:45:33 Journal contribution https://bridges.monash.edu/articles/journal_contribution/Line_of_sight_analysis_for_urban_mobile_applications_a_photogrammetric_approach/5544427 Although inter visibility analysis between a GPS receiver and visible satellites is crucial for any real-time route navigation, traditional, mission-planning software does not incorporate it – they simply assume that the earth is flat. This paper seeks to correct the situation by outlining an advanced, semi-global matching technique which derives a Digital Surface Model (DSM), depicting the topography model of the earth surface for any study area. Our approach uses a GIS, combined with a freely available Global Navigation Satellite System (GNSS), to accurately predict pseudo satellite locations before building three-dimensional models of buildings from their footprints. We exploit high-resolution satellite data (Cartosat-1 and Geoeye-1) along with high-density elevation information, and we ultimately reduce the need for full-scale surveys and so minimize costs and time. Moreover, our combining of 3D models with GPS-derived, ephemeris data pertaining to densely built-up areas constitutes a valuable input for real time, mobile applications like car navigation systems, personal navigation, fleet tracking, asset tracking and general, location-based services.