Satellites

Basics

Elliptical or circular orbits.

Complete rotation time depends on distance satellite-earth.

Inclination: angle between orbit and equator.

Elevation: angle between satellite and horizon.

LOS (Line Of Sight) to the satellite is necessary for connection.

• high elevation needed, less absorption due to obstacles.

Uplink: connection base station - satellite.

Downlink: connection satellite - base station.

Typically separated frequencies for uplink and downlink

• transponder used for sending/receiving and shifting of frequencies.

• transparent transponder: only shift of frequencies.

• regenerative transponder: additionally signal regeneration.