HOW THE MICROPROCESSOR SATELLITE
What's Microprocessor?
- Microprocessor or CPU is the "brain" which is the main controlling all operations in the satellite system. Microprocessor taking the binary instructions from memory, translated into a series of action and run it. The action could be a transfer of data to and from memory, arithmetic and logic operations, or the generation of control signals.
FIGURE 1
MICROPROCESSOR SATELLITE
SATELLITE POSITION
Position of the satellite in its orbit is divided into 3 kinds.
- 1. Low Earth Orbit (LEO): 500 to 2.000 km above the earth's surface.
2. Medium Earth Orbit (MEO): 8.000 to 20.000 km above the Earth's surface.
- 3. Geosynchronous Orbit (GEO): 35.786 km above the Earth's surface.
HOW THE SATELLITE
Phase I. The satellite receives radio signals from earth stations (up link)- Earth stations transmit data that has been in the encoding into a radio signal, via a parabolic reflector is emitted towards the satellite. , Earth station antenna is placed on the outdoor section in the direction of a straight line to the satellite (line of sight) without any obstructions.- The transmitter creates a powerful burst of energy in the form of radio waves that can travel through the Earth's atmosphere to a satellite in space, satellite antenna is a tool such as the curved dish (parabolic antenna) receives a radio signal transmitted from the earth station antenna. The radio signal is emitted in the power spectrum at a predetermined frequency satellite communications system used.II. Signal processing stage in the transponder· The radio signals being picked up by a satellite antenna forwarded to the transponder. In the transponder radio signal is processed by a variety of electrical components such as the following:· Input select band pass filter limits band / frequency range of the input radio signal on the uplink, passing frequencies within a certain range that is applied to the system and reject (attenuate) frequencies outside that range.· LNA (Low Noise Amplifier), amplify the input radio signal is weak because of large distances traversed the received radio signals from the ground station· Frequency translator, expand and convert the received radio frequency signal (uplink) to the specified frequency for the transmitted signal (down link frequency) to a ground station. This is so the signal uplink and down link signals flow with their own, not diffuse.· Power amplifier in the form of a traveling wave tube or a Travelling Wave Tube (TWT) so it is also known as TWTA (Traveling Wave Tube Amplifiers) or solid state amplifier is a special vacuum tube amplify radio frequency (RF) signals to high power.· The band pass filter selects the output frequency range limit output in the downlink radio signal, radio signal passed with a certain frequency range· Demux (demultiflexer) is a digital switch with a single input (source) and multiple outputs (destinations). Signal at the input will be routed to the output (channel) which depends on the control on the part of its Select.
III. Phase Satellites transmit / re transmit the radio signals to Earth (down link)· The radio signals that have undergone a process of refinement, strengthening and setting specific down link frequency will be transmitted back to Earth via a satellite antenna. In the process of satellite communications signals no change. The transmitted signal remains the same as it is received. All the satellite has an onboard computer to control and monitor different systems - depending on satellite systems such as radios and antennas. All systems have an attitude control system that makes satellite is working properly.· The radio signals sent back by the satellite to a ground station signal sender or to another earth stasion appropriate allocation functions and satellites that have been set in the making.· The signals received by the earth station antenna and decoded by a decoder tool is then processed by a computer system for their designated purpose.
Illustration of signal levels ranging from the sender, satellites to receivers on earth.
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understanding Waves
Waves are vibrations that propagate. The hallmark of each wave is a wave energy propagation . In wave mechanics, it is shown when energy is propagated through water waves capable of moving the original cork floating quietly on the water's surface. ships at sea are often caused by ocean waves prove the amount of energy carried by the waves. Heat from the sun feels on earth we are also caused by electromagnetic waves emitted by the sun propagate or radiate heat energy to the earth.Meanwhile, the transport of energy through electromagnetic waves without realizing its benefits are commonly enjoyed in everyday life. For example, one can enjoy the music of distant radio station for their radio waves that carry sound energy that music.Thanks to the micro wave, someone can give orders to his company officer and control only of a cell phone. All means of communication is made possible through electromagnetic waves, which can transport energy information to various places.- Various WavesBased on the direction of vibration:
A transverse wave, the wave direction of vibration perpendicular to the direction propagation.
Longitudinal waves, the wave direction of vibration in the direction propagation.
Based on how the vines and the medium through which:
Mechanical waves, which are propagated waves and wave mechanics necessary for propagation medium.
Electromagnetic waves, the waves are propagated is the electric field magnet, and is not required medium.
Based on the amplitude:
Wave, the wave amplitude is fixed at a point in its path.
Stationary wave, the wave amplitude is not fixed at a point in its path, which is formed from the interference of two waves coming and reflected that each have the same frequency and amplitude but opposite phase.
From some of the information the author tries to find some benefits in particular for electromagnetic waves waves
Identification of Electromagnetic WavesElectromagnetic waves are waves that can propagate even if there is no medium. Electromagnetic energy travels in waves with some characters that can be measured, namely: wavelength / wavelength, frequency, amplitude / amplitude, speed. Amplitude is the height of the wave, while the wavelength is the distance between two peaks. Frequency is the number of waves passing through a point in unit time.The frequency depends on the speed of the wave climbed. Because electromagnetic energy is a constant velocity (speed of light), wavelength and frequency is inversely proportional. The longer a wave, the lower the frequency, the shorter the wave and the higher frequencies.Electromagnetic energy emitted or released, by all the time in the universe in which different levels. Higher levels of energy in an energy source, the lower the wavelength of the energy produced, and the higher frequencies. Different characteristics of the wave energy is used to classify electromagnetic energy.- Characteristics of Electromagnetic Waves
Changes in electric field and magnetic field occurs at the same time, so that the two fields have a maximum and minimum prices at the same time and in the same place.
Direction of the electric field and magnetic fields perpendicular to each other and both perpendicular to the direction of propagation.
Of characteristic No. 2 shows that the electromagnetic waves are transverse waves.
Like the waves in general, an incident electromagnetic wave reflection, refraction, interference, and diffraction. Also an incident polarization because it includes a transverse wave.
Rapid propagation of electromagnetic waves depends only on the properties of electric and magnetic medium is taken.
- Spectrum of Electromagnetic WavesThe composition of all forms of electromagnetic waves by wavelength and frequency is called the electromagnetic spectrum. Examples of the electromagnetic spectrum:1) Wave RadioThe radio waves are classified according to wavelength or frequency. If the wavelength is high, then surely the low-frequency or vice versa. Radio frequency ranging from 30 kHz up and grouped according to the width of the frequency. The radio waves generated by electric charges are accelerated through conductive wires. Charges are generated by an electronic circuit called an oscillator. The radio waves emitted from the antenna and received by an antenna anyway. You can not hear the radio directly, but will change the radio receiver first wave energy into sound energy.2) MicrowavesMicrowaves (microwaves) are radio waves with the highest frequency is above 3 GHz. If the microwaves are absorbed by an object, it will appear the warming effect on the thing. If the food absorb microwave radiation, the food hot in a very short time interval. This process is used in a microwave oven to cook food quickly and economically.Microwaves are also used on aircraft RADAR (Radio Detection and Ranging) RADAR means finding and determine the trace of an object by using microwaves. Aircraft radar utilizing the reflectance properties of microwaves. Due to the rapid propagation of electromagnetic wave c = 3 X 108 m / s, then by observing the time interval between transmitting the reception.3) Infrared raysInfrared light covers an area up to 1014 Hz 1011Hz frequency or wavelength regions 10-4 to 10-1 cm cm. if you check the spectrum produced by an incandescent lamp with a detector which is connected to the miliampere meter, then the needle ampere meter slightly above the red end of the spectrum. Rays are not visible but can be detected above the red spectrum is called infrared radiation.Infrared rays produced by electrons in molecules vibrate because to hot objects. So any hot objects emit infrared rays certainly. The amount of infrared light emitted depends on the temperature and color of objects.4) Visible lightVisible light as electromagnetic radiation that is most familiar to us can be defined as part of a spectrum of electromagnetic waves that can be detected by the human eye. visible wavelengths depending on the color wavelengths ranging from approximately 4 x 10-7 m to light violet (purple) to 7x 10-7 m for red light. Usefulness light one of them is use of lasers in optical fiber telecommunications and medicine.5) UltravioletUltraviolet light has a frequency in the range 1015 Hz to 1016 Hz or in a wave of 10-8 m long area 10-7 m. The waves generated by atoms and molecules in electric flame. The sun is source .
Application of Electromagnetic Waves
The radio waves emitted from the transmitting antenna and received by the receiving antenna. The area is covered and the resulting wavelengths can be determined by high and low antenna. Radio waves can not directly be heard, but this energy is to be converted into sound energy by air as a radio receiver. The use of radio waves for communication are shown in the following figure
Television waves have higher frequencies than radio waves. This television waves propagate straight, can not be reflected by the layers of the earth's atmosphere. Television waves is widely used in the fields of communications and broadcasting. In the process of catching telecast often necessary liaison station (relay) in order to arrest the picture and sound better..
Micro-wave (microwave) has a frequency of 3 GHz. Microwaves can be used for communication tools, cooking, and radar. Radar is an acronym for Radio Detection and Ranging. Radar antenna can act as a transmitter and receiver of electromagnetic waves. At the air base, the radar transmitter antenna can rotate in all directions to detect aircraft heading or leave the air base. In the field of transport, the radar waves are used to help smooth air traffic in the air base or airport. Wave radar is used also in the field of defense is to equip fighter aircraft so they can know the whereabouts of the enemy planes.
The infrared light is the result of vibrational or rotational transitions in molecules. Infrared light includes electromagnetic waves having a frequency infrared light is not visible to the naked eye but visible infrared rays can be detected by using plates of a particular film that is sensitive to infrared waves. High-flying aircraft or satellites can make image photo the earth's surface, using infrared waves. As well as ultraviolet rays and visible light, infrared rays are also widely used in the field of spectroscopy to determine the elements in the material.
Visible light is often also referred to as light. Visible light includes electromagnetic waves having a frequency between ultraviolet rays is the result of transitions of electrons in atoms or molecules skin. The sun is a natural source of visible light. Visible light is composed of a variety of colors, from red, orange, yellow, green, blue, and purple. We can all see the color of the object because the object reflects these colors and go back to our eyes. Many applications of light in our lives, among others, by the light we can see the beautiful scenery, we can take pictures so that the picture becomes colored as the original, we can see a color television, and so on. As well as ultraviolet light, visible light is widely used also in the field of spectroscopy to determine the elements in the material.
Ultraviolet rays including electromagnetic waves having a frequency of ultraviolet light is the result of transitions of electrons in atoms or molecules skin. Ultraviolet rays do not appear visible to the naked eye but these rays can be detected by using plates of a particular film that is sensitive to ultraviolet waves. The sun is a natural source of ultraviolet radiation. Ultraviolet light produced by the sun is not good health, especially if the human skin. Humans are protected from ultraviolet rays of the sun because of the ozone layer in the atmosphere that absorbs ultraviolet rays. Applications ultraviolet light is widely used in laboratory research spektroskopi field, one example to determine the elements present in certain materials.
X-rays discovered by Wilhelm Conrad Rontgen in 1895 so it is often referred to as the Rontgen rays. X-rays including electromagnetic waves having a frequency between
X-ray is the result of the transition electron electron in the inner skin, the transition occurs in the atom. X-rays have the second largest after the penetrating power of gamma rays. X-rays can penetrate human flesh. Rays are often used in the medical field to check patients .
X . II
Working mode satellite
Working mode COSPAS-SARSAT satellite
Real time above 121.5 MHz repeater system: a satellite repeater on 121.5 Mhz transmits signals directly to the LUT station without going through the process. LUT and EPIRB must be within direct view of the satellite, a new signal can be processed in the LUT position.
Real time data is 406 Mhz proccessed system: Satellite receives signal 406 MHz, the data is immediately processed dopper position by shifting frequency, position data are transmitted to the LUT station located at a distance of vision.
Global 406 Mhz Coverage Mode: By storing the data on the position beacons COSPAS memory, these satellites can provide data on the position of the signs on all active in cross LUT.
Diagram sattelite com
Figure Assigned Frequency in NBDP system
Assigned Frequency is the center frequency emitted by adding or subtracting a frequency of approximately 85 Hz to form the Space and Mark.
Carrier Frequency is the carrier wave to be modulated by Telex system using Frequency Shift Keying (FSK).
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