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LEO Satellites

Icom’s PTT Satellite radios operate on Iridium’s Low Earth Orbit Satellites (LEO). LEO provides low latency communication, broader and more reliable network coverage compared to Geosynchronous Equatorial Orbit Satellites (GEO), which need more variables to operate. GEO satellites are affected by the weather such as rain, clouds and snow. They also do not cover both North and South Poles.

LEO Benefits:

  • Lower latency compared to GEO
  • Stronger signals compared to GEO
  • Portable antenna
  • No need to face south

Characteristics of Iridium LEO Satellites

  • 66 LEO (Low Earth Orbit) satellites circulating the earth at 780 km of altitude
  • Each fast moving (27000 km/h) satellites completes an orbit around the Earth every 100 minutes; accessible from a radio approx. for 10 minutes and then the next satellite takes over
  • Line-of-sight to the satellite may be blocked by structure or terrain and the link lost
  • Since it is moving fast, connection will be re-established typically less than a minute.