Mohammed Eltahir's blog

Introduction Global Navigation Satellite System (GNSS) is an umbrella term that include vase range of satellite navigations system that provide geospatial and positioning data in a global range covering, systems such as: GPS (USA) , GLONASS (Russia), QZSS (Japan) ...etc. Here well define the European Geostationary Navigation Overlay Service (EGONS) as an example of GNSS,its history, system segments, explore satellites names and their signals, navigation, Reference from and time and accuracy. Definition The European Geostationary Navigation Overlay Service (EGNOS) is a  satellite based augmentation system  (SBAS) developed by the  European Space Agency  and  EUROCONTROL . It was intended for general Purpose application and freely accessible. also supply GPS, GLONASS and Galileo by sending report about their reliability and accuracy of their positioning data and provide corrections History The system started in 2009 after the European Commission signed...

Introduction : Using satellites in fish harvesting is due to the great advantages they provide such as the wide range capture of see surface “large coverage”, temporal resolution and data are independent from weather. So that remote sensing has real impact on uncovering the relationship between fish distribution and surrounding environment. The main objective of using remote sensing is to reduce search time and increase catch rate. There are two methods to apply remote sensing data: Indirect Method: measuring oceanographic and environmental factors that correlate with fish habitat, such as ocean colour, sea surface temperature (SST), wind stress, current data, and other environmental characteristic that affect fish habitat Also, known the fact that fish correlate with nutrient-rich waters. Direct method: by spotting fish appearance.  Measuring the environmental factors is much easier than spotting the appearance of a fish. And the main source for fisheries management is thermal...