Week-4-5-Global-Navigation-System.pdf
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Department of Environmental Science and Technology College of Science and Mathematics University of Science and Technology of Southern Philippines-CDO Campus Learning Outcomes Understand the standard generic term for satellite navigation systems that provi...
Department of Environmental Science and Technology College of Science and Mathematics University of Science and Technology of Southern Philippines-CDO Campus Learning Outcomes Understand the standard generic term for satellite navigation systems that provide autonomous geospatial positioning with global coverage. Acquire necessary technique to improve accuracy of GNSS errors Outline Systems of Navigation in the past Construction of monuments. Construction of detailed maps. Interpreting stars. Coordinate system give us numbers Global Navigation System the standard generic term for satellite navigation systems that provide autonomous geospatial with global coverage refers to constellation of satellites providing signals from space transmitting positioning and timing data consists of three segments - satellites, ground station, and users satellites - constellation of satellites orbiting the Earth and also known as space segment ground stations – track and monitor the satellites and is also known as control segment users - rely on the satellites to compute for their position and motion GNSS Framework Space – control segment has bidirectional signal Space – user segment has one way signal Principles of satellite-based navigation Geocenter – receiver is known Geocenter – satellite is known (hypotenuse) Defined by trigonometric functions. Principles of satellite-based navigation Q = C (Travel Time) Where; C = speed of light (m/s) Time = s Q = distance between receiver and satellite (m) Defined by trigonometric functions. You are 625 miles from Boise, Idaho. You are 690 miles from Minneapolis, Minnesota. If a third person tells you that you are 615 miles from Tucson, Arizona, https://electronics.howstuffworks.com/gadgets/travel/gps.htm#pt1 Best Practices when using GPS Clear view of the sky (no trees) At least it captures 4 satellites At least maintain a distance far away from tall buildings. Hold it flat and don’t move (put it in the ground). Fixed a location for 20 seconds before recording the point. Cold war sparks space race: The case of US and USSR rivalry Nuclear war/bombing crisis (e.g., Cuban nuclear missile war crisis). US planes are continually shutdown. Implementation of a classified satellite imagery (CORONA spy satellite 1960 - 1972). Earthexplorer.com Coverage and frequency of shots b. Globalnaya Navigazionnaya Sputnikovaya Sistema (GLONASS) Operated by the Russian Aerospace Defense Forces, Russia. Has 24 satellites in operation (with 3 spares) Provides better coverage at higher latitude. ØSPS (Standard Positioning Service) ØPPS (Precise Positioning Service) Collapse following Soviet Union economic crisis in the 90s (related to oil peak crisis). The End……………..
