37. What is the period of the Moon, according to Kepler’s law? Example 16.1 Here C is a constant approximately equal to 1/100. The period is in seconds and the distance in kilometers.
38. According to Kepler’s law, what is the period of a satellite that is located at an orbit approximately 35,786 km above the Earth? Example 16.2 Solution Applying the formula, we get
39. Classical satellite systems base station or gateway Inter Satellite Link (ISL) Mobile User Link (MUL) Gateway Link (GWL) footprint small cells (spotbeams) User data PSTN ISDN GSM GWL MUL PSTN: Public Switched Telephone Network
41. Elevation Elevation: angle between center of satellite beam and surface minimal elevation: elevation needed at least to communicate with the satellite footprint
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43. Atmospheric attenuation Example: satellite systems at 4-6 GHz elevation of the satellite 5° 10° 20° 30° 40° 50° Attenuation of the signal in % 10 20 30 40 50 rain absorption fog absorption atmospheric absorption
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45. Orbits II earth km 35768 10000 1000 LEO (Globalstar, Irdium) HEO inner and outer Van Allen belts MEO (ICO) GEO (Inmarsat) Van-Allen-Belts: ionized particles 2000 - 6000 km and 15000 - 30000 km above earth surface
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50. What’s on a satellite? Communications Power Sensors/Instruments “ Bus”
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Editor's Notes
EIRP: Equivalent isotropically radiated power or Effective isotropic radiated power is the amount of power that a theoretical isotropic antenna (that evenly distributes power in all directions) would emit to produce the peak power density observed in the direction of maximum antenna gain. EIRP can take into account the losses in transmission line and connectors and includes the gain of the antenna. The EIRP is often stated in terms of decibels over a reference power emitted by an isotropic radiator with an equivalent signal strength.
