Satellites
How do they work?
NAVSTAR Global Positioning System Satellite
Uses
DirectTV, DBSNewsTelephonesCableGPSEmergency radio beacons
Components
ANY object that revolves around a planet (e.g. the moon)ArtificialOrbit, Apogee, and PerigeeCustom built“Space junk”
Sputnik 1 (October 4, 1957)
Soviet Union A Thermometer A Battery A Radio
transmitter Pressurized
Nitrogen gas
3, 2, 1, Lift-off (Launch)
Rockets and the space shuttleOrbital Velocity and AltitudeLaunch Window
Types
Weather satellites (TIROS, COSMOS)Communications satellites (Telstar, Intelsat) transponder
Broadcast satellitesScientific satellites (Hubble telescope)Navigational satellites (GPS Navstar)Rescue satellitesEarth observation satellites (LANDST)Military satellites (???)
Components
Frame/Body (Bus)
Power source
Computer
Communications
Attitude control system (ACS)
Geostationary Orbits
Positioned over the same area
Normally, 22,223 MilesWeather
Communication
Communications Satellite
Asynchronous Orbits
Multiple passes80-1,200 miles Teledesic, LEOs
Observation (300-600 miles)3,000-6,000 miles Scientific
6,000-12,000 miles Navigation (GPS)
Polar Orbit
Low altitudePasses over the poles on each orbitMapping and photography
Teledesic: Low Earth Orbit Satellites (LEOs)
Network of Constellations“Internet-in-the-SkyTM”
LEO Coverage
288 operational satellites, divided into 12 planes with 24 satellites each
LEO Service
Optical Intense coverage Inter-Satellite Links
Next Generation (Northpoint)
Northpoint TechnologyTerrestrial satellite
Northpoint
Current: Multiple
towers
Northpoint “cellular
network”
Northpoint Impact
Competition with cable and DBSFiber optics to allOpportunities for Geostationary satellitesSpectrum planning
Broadwave USA Inc.
Local serviceLocal and National ProgrammingCheaper