geinGHzrange.(Uplink)SatelliteReceiveandretransmitsignalsback.(Downlink)OtherEarthStationsreceivemessageinusefulstrengtharea.(Footprint)SatelliteFrequencyBandsandAntennas(Dishes)ThesizeofSatelliteDishes(antennas)arerelatedtothetransmissionfrequency.Thereisainverserelationshipbetweenfrequencyandwavelength.Aswavelengthincreases(andfrequencydecreases),largerantennas(satellitedishes)arenecessarytogatherthesignal.SatelliteFrequencyBandsandAntennas(Dishes)C-Band Ku-monlyusedbands:C-band(4to8GHz),Ku-band(11to17GHz),andKa-band(20to30GHz).Low-Earth-Orbit(LEO)Altitude(375-1000miles)Revolutiontime:90min-3hours.Advantages:ReducestransmissiondelayEliminatesneedforbulkyreceivingequipment.Disadvantages:Smallercoveragearea.Shorterlifespan(5-8yrs.)thanGEOs(10yrs).Subdivisions:Little,Big,andMega(Super)LEOs.
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