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FACULTY OF ENGINEERING
DEPARTMENT OF AEROSPACE ENGINEERING
EAS3802 SATELLITE TECHNOLOGY
SEMESTER 2, 2012/2013
LECTURER: PROF. IR. DR. HARIJONO DJOJODIHARDJO
ASSIGNMENT 4
DATE: 22/04/2013
NAME: CHAN TENG YAN
MATRIC NO.: 157388
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1. Remote sensing
Remote sensing is the acquisition of information about an object or phenomenon without
making physical contact with the object. In modern usage, the term generally refers to
the use of aerial sensor technologies to detect and classify objects on Earth (both on the
surface, and in the atmosphere and oceans) by means ofpropagated
signals (e.g. electromagnetic radiation emitted from aircraft orsatellites).
2. What is transponder? Relate with uplink and downlink signal?
Transponder electronics in the satellite that convert uplink signals to downlink signals.
3. Describe uplink and downlink signal
Uplink frequency: In satellite telecommunications terminology, uplink means the signal
sent from Earth to the satellite.
Downlink frequency: In satellite telecommunications terminology downlink means the
signal from the satellite to earth.
4. How would the signal be transmitted when we communicate with friend at US?
Block Up Converter, is part of the uplink side. Uplink means from earth to satellite. The
BUC puts the signal on a "carrier" frequency which is an SHF (super high frequency)
signal. SHF is the frequency range in which satellites operate on (3GHz to 30GHz).
The LNB, or Low Noise Block converter, is part of the downlink side (satellite to earth).
Since the antenna receives all the frequencies its satellite is transmitting, a filter is
needed. The LNB only lets through the block of frequencies needed.
So here's the signal flow starting from earth.
5. How many geostationary orbit to cover the entire earth?
6. Solar wind
The solar wind is a stream ofcharged particles released from the upper atmosphere of
the Sun. It mostly consists ofelectrons and protons with energies usually between 1.5
and 10 keV. The stream of particles varies in temperature and speed over time. These
particles can escape the Sun's gravity because of their high kinetic energy and the
high temperature of the corona.
http://en.wikipedia.org/wiki/Atmospherehttp://en.wikipedia.org/wiki/Oceanshttp://en.wikipedia.org/wiki/Wave_propagationhttp://en.wikipedia.org/wiki/Wave_propagationhttp://en.wikipedia.org/wiki/Electromagnetic_radiationhttp://en.wikipedia.org/wiki/Aircrafthttp://en.wikipedia.org/wiki/Satelliteshttp://en.wikipedia.org/wiki/Charged_particlehttp://en.wikipedia.org/wiki/Stellar_atmospherehttp://en.wikipedia.org/wiki/Sunhttp://en.wikipedia.org/wiki/Electronhttp://en.wikipedia.org/wiki/Protonhttp://en.wikipedia.org/wiki/Electronvolthttp://en.wikipedia.org/wiki/Gravityhttp://en.wikipedia.org/wiki/Kinetic_energyhttp://en.wikipedia.org/wiki/Temperaturehttp://en.wikipedia.org/wiki/Coronahttp://en.wikipedia.org/wiki/Coronahttp://en.wikipedia.org/wiki/Temperaturehttp://en.wikipedia.org/wiki/Kinetic_energyhttp://en.wikipedia.org/wiki/Gravityhttp://en.wikipedia.org/wiki/Electronvolthttp://en.wikipedia.org/wiki/Protonhttp://en.wikipedia.org/wiki/Electronhttp://en.wikipedia.org/wiki/Sunhttp://en.wikipedia.org/wiki/Stellar_atmospherehttp://en.wikipedia.org/wiki/Charged_particlehttp://en.wikipedia.org/wiki/Satelliteshttp://en.wikipedia.org/wiki/Aircrafthttp://en.wikipedia.org/wiki/Electromagnetic_radiationhttp://en.wikipedia.org/wiki/Wave_propagationhttp://en.wikipedia.org/wiki/Wave_propagationhttp://en.wikipedia.org/wiki/Oceanshttp://en.wikipedia.org/wiki/Atmosphere7/29/2019 Satellite Assignment 4
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The solar wind creates the heliosphere, an enormous bubble in the interstellar
medium that surrounds the Solar System. Other related phenomena
include geomagnetic storms that can knock out power grids on Earth,
the aurora (northern and southern lights), and the plasma tails ofcomets that always
point away from the Sun.
7. Solar sailing
Solar sails (also called light sails or photon sails) are a form of spacecraft propulsion
using the radiation pressure (also called solar pressure) of a combination of light and
high speed ejected gasses from a star to push large ultra-thin mirrors to high speeds.
Light sails could also be driven by energy beams to extend their range of operations,
which is strictly beam sailing rather than solar sailing.
Solar sail craft offer the possibility of low-cost operations combined with long operating
lifetimes. Since they have few moving parts and use no propellant, they can potentially
be used numerous times for delivery of payloads.
Solar sails use a phenomenon that has a proven, measured effect on spacecraft. Solar
pressure affects all spacecraft, whether in interplanetary space or in orbit around a
planet or small body. A typical spacecraft going to Mars, for example, will be displaced
by more than 1,000 km by solar pressure, so the effects must be accounted for in
trajectory planning, which has been done since the time of the earliest interplanetary
spacecraft of the 1960s. Solar pressure also affects the attitude of a craft, a factor that
must be included in spacecraft design.
8. Jet propulsion
( )
http://en.wikipedia.org/wiki/Heliospherehttp://en.wikipedia.org/wiki/Interstellar_mediumhttp://en.wikipedia.org/wiki/Interstellar_mediumhttp://en.wikipedia.org/wiki/Solar_Systemhttp://en.wikipedia.org/wiki/Geomagnetic_stormhttp://en.wikipedia.org/wiki/Aurora_(astronomy)http://en.wikipedia.org/wiki/Plasma_(physics)http://en.wikipedia.org/wiki/Comethttp://en.wikipedia.org/wiki/Comethttp://en.wikipedia.org/wiki/Plasma_(physics)http://en.wikipedia.org/wiki/Aurora_(astronomy)http://en.wikipedia.org/wiki/Geomagnetic_stormhttp://en.wikipedia.org/wiki/Solar_Systemhttp://en.wikipedia.org/wiki/Interstellar_mediumhttp://en.wikipedia.org/wiki/Interstellar_mediumhttp://en.wikipedia.org/wiki/Heliosphere7/29/2019 Satellite Assignment 4
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