Satellite Antennas/Spacecraft Antennas
Spacecraft antennas are mounted on the body of the spacecraft(i.e.satellite) to provide coverage on specific region of the earth. Based on the applications different types of antennas are designed and tested and fitted on spacecraft before the launch of the satellite in the space. Different applications include TTC(Telemetry,Tracking and Command), communications and metreological data collection and for research on the lands and oceans.
Satellite antennas include monopole antenna, dipole horn antenna, reflector antenna,patch antenna,dish antenna and helix antenna as mentioned in the table below. Below is the list of antennas used on indian INSAT series of satellites developed by ISRO.
• INSAT- 1D - Horn/dish antennas for C band, Circular Patch/dish antennas for UHF band, Helix for ground station applications
• INSAT-2A - Horn/Dish antenna for C band
• INSAT-2B - Horn/Dish,Circular patch antennas for UHF band
Earth Station Antennas are usually of high gain and generates very narrow beam so that
it can point towards the satellite.
Monopole and dipole antennas are used for omnidirectional application in VHF/UHF frequency range for TTC application.
Horn antennas are required to generate wide beam so that large area of the earth can be covered by them.
Reflector antennas and array of pointed antennas are used when high gain or narrow beamwidth is required.
usually in a satellite/spacecraft one beam is needed to cover one earth station so if multiple earth stations are there than it requires multiple such beams to be transmitted/received by spacecraft. INTELSAT V spacecraft has 4 such reflector antennas for 4 beams which takes care of many earth stations in one region of the earth.
Shape of the beam depends on the frequency emitted by the satellite/spacecraft. To generate zone beams 4GHz is needed and to generate spot beams 14 or 11 GHz is needed.
For satellite related terms, refer satellite terminology page.
For satellite function, frequency bands, satellite network, parts, orbits, services, types, capacity allocation ,network configurations and satellite applications, refer satellite tutorial
For Low Noise Block Converter basics and LNB manufacturer, refer our page on LNB.