what is satellite communication?
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A radio relay station in orbit above the earth that receives, amplifies and redirects analog and digital signals contained within a carrier frequency. There are three kinds. Geostationary (GEO) satellites are in orbit 22,282 miles above the earth and rotate with the earth, thus appearing stationary. The downlink from GEOs back to earth can be localized into small areas or cover as much as a third of the earth's surface.\n\nLow-earth orbit (LEO) satellites reside no more than 1,000 miles above the earth and revolve around the globe every couple of hours. They are only in view for a few minutes, and multiple LEOs are required to maintain continuous coverage. Medium-earth orbit (MEO) satellites are in the middle, taking about six hours to orbit the earth and in view for a couple of hours.\n\nI hope this helps...\n\nDon
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Do we need anymore?  Maybe its just not an item we need seeming how we now have satellites over the ocean.  Good question
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I'm sure you mean can anyone copy it. Yes, I could when I was in the military. I learned it at the age of 18 through a 26 week tech school. It's no longer the way the main line world communicates. It's just for fun now. The world communicates by satelite.
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Data communications deals primarily with data.\n\nTelecommunications deals primarily with voice.\n\nWhile these two areas of study have always had a number of overlapping concepts, they have never been closer than they are right now. It is increasingly difficult to separate one from the other.
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You need a big dish antenna and a lot of power to transmit to a geo satellite.  If your cell phone had that, it would be to0 big and heavy to carry.  That's why towers combine calls from many different users and route them, as needed, to other towers via wires, microwaves, or satellite communications.
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Communication allows transmission of data and information to the decision makers.
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If the satellite is designed for use in GEO, It would not be much use in any other orbit. That is because satellites in GEO are always in the same part of the sky as seen from the ground. Home TV broadcast satellites are in GEO, so you just have to point your dish antenna at the satellite when you install it and then fix it permanently it in place. To communicate with a satellite in any other orbit you have to have a computer controlled motorized antenna that follows the satellite as it moves across the sky. And the moving satellite will rise and set, like the sun, and be impossible to communicate with it when it is below the horizon, because radio signals travel in strait lines and cannot go through the Earth. In very low orbits the satellite may be above the horizon at your city for only few minutes each week!
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Electronic communication systems form the "nervous system" of Earth's communication system.  It allows for quick, reliable communication by e-mail, instant messaging, file sharing, and video confrencing to virtually any location.  Lastly, electronic communication systems forms the basis of the global economy since data can quickly be delivered to another continent.
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I think the last person that answered misunderstood the question.  I believe you mean the XM and Sirius satellite radio.  The channels are the same no matter where you go, the same name and the same channel number.  It is different from FM/AM radio as there could be other stations use the same frequency but in another region.  Satellite radio is meant to broadcast all over the U.S. as FM/AM is not meant to.  \n\nIt is the same with television stations.  If you receive it on a cable system or over the air that channel is unique to that area but if you get Dish Network or DirecTv that station and number is the same no matter where you go in the U.S. and receive that signal.
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Yes, you can downlink fro a satellite.  However most people do not have a sufficient power plant to uplike to a satellite.  There you need a hard wired connection,.
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gsm is the old system to connect cellular phone with a satellite\n\ngprs is a new system for cellular phone - satellite \nwith this system the date trasmit more speed\n\nbluetooth is a system to connect a eletronic stuff near another
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A specialized network server that provides access to resources on the network for users not directly attached to the network or that permits network users to access external resources not directly attached to the network.\n\nCommunication may be Internet, dial-up or other methods.
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Satellite Telecom.  Companies have invested a lot of money in developing the infrastructure.  By the time they have it set up the sat phones will be comparable to regular Cell phones.
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Advantages: Bring communication from the outside world to those who are isolated by geography or political repression but have the necessary receiving equipment. Such communications can educate; can save lives by warning about impending natural disasters; can inspire change by relating the lives of those in freer societies. Imaging and directional RF receiving satellites can help search and rescue, evacuation planning. \nDisadvantages: Every potentially advantageous function can be used disadvantageously. Can enable repressive regimes to propagandize, spy, direct weapons fire.
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Radio is the wireless transmission of signals, by modulation of electromagnetic waves with frequencies below those of light.\n\nRadio propagation is a term used to explain how radio waves behave when they are transmitted, or are propagated from one point on the Earth to another.\n\nIn free space, all electromagnetic waves (radio, X-rays, visual, etc) obey the inverse-square law which states that an electromagnetic wave's strength is proportional to 1/(x2), where x is the distance from the source. Doubling the distance from a transmitter means the strength is reduced to a quarter, and so on.\n\nRadio propagation on Earth is not only affected by the inverse-square model, but by a number of other factors determined by its path from point to point. This path can be a direct line of sight path or an over-the-horizon (see also radio horizon) path aided by reflection from the ionosphere. A variety of phenomena make radio propagation more complex.\n\nSince radio propagation is somewhat unpredictable, such services as emergency locator transmitters, in-flight communication with ocean-crossing aircraft, and some television broadcasting have been moved to satellite transmitters. A satellite link, though expensive, can offer highly predictable and stable coverage of a given area.\n\nA sudden ionospheric disturbance is often the result of large solar flares directed at earth. These solar flares can disrupt HF radio propagation\n\nThe Antenna\nThe beginning and end of a communication circuit is the antenna. The antenna will provide gain and directivity on both transmit and receive. The take off angle of the antenna is based on the type of antenna, the height of the antenna above ground, and the type of ground below and in front of the antenna. The take off angle will determine the angle of attack on the ionosphere, which will effect if and where the signal will be reflected by the ionosphere.\n\nGround wave Propagation\nGround waves are radio waves that follow the curvature of the earth. Ground waves progress along the surface of the earth and must be vertically polarized to prevent short circuiting the electric field through the conductivity of the ground. Since the ground is not a perfect electrical conductor, ground waves are attenuated as they follow the earth’s surface. At low frequencies, ground losses are low and become lower at lower frequencies. The VLF and LF frequencies are mostly used for military communications, especially with ships and submarines.\n\nEarly commercial and professional radio services relied exclusively on long wave, low frequencies and ground-wave propagation. To prevent interference with these services, amateur and experimental transmitters were restricted to the higher (HF) frequencies, felt to be useless since their ground-wave range was limited. Upon discovery of the other propagation modes possible at medium wave and short wave frequencies, the advantages of HF for commercial and military purposes became apparent. Amateur experimentation was then confined only to authorized frequencies in the range.\n\nLine-of-Sight Propagation\nGround plane reflection effects are an important factor in VHF line of sight propagation. The interference between the direct beam line-of-sight and the ground reflected beam often leads to an effective inverse-fourth-power law for ground-plane limited radiation.\n\nSkywave Propagation\nSkywave propagation is any of the modes that rely on reflection of radio waves from the ionosphere, which is made up of one or more ionized layers in the upper atmosphere. These layers are directly affected by the sun, and its varying activity (sunspot cycle) determines the utility of these modes. Forecasting of skywave modes is of considerable interest to amateur radio operators and commercial marine and aircraft communications, and also to shortwave broadcasters.\n\nTropospheric Scattering\nAt VHF and higher frequencies, the atmosphere at a height of around 6 miles (10 kilometres) can scatte
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Are you refering to communication to submarines.\n\nCheck out the ELF project, extremely low frequency telecommunications.
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A satellite is something that orbits a planet or star.\norbiting involves moving around that object fast enough so that the satellite's rate of descent toward the planet is balanced with its speed so it stays the same distance from the planet(or star).\nSatellites like dishnetwork satellites follow the earth's rotation, by orbiting very high. this lets them essentially stay in one spot to an observer on the earth.\n\nman made satellites receive and send information on parabolic dishes to strengthen their connection.\nother than that, you are on your own.