Augmented Reality Satellite Finder Out Now Watch this video, its very surreal. This is the next generation satellite finder Point your iPhone anywhere towards. Links to satellite imagery for the Atlantic basin from sites like NOAA, NASA, SSEC, EUMETSAT, CIMSS, NRL and others. A communications satellite is an artificial satellite that relays and amplifies radio telecommunications signals via a transponder it creates a communication channel. Operating the most agile and sophisticated commercial satellite constellation in orbit, DigitalGlobe put the worlds smartest images into your hands. Weve found the absolute best satellite internet providers available. See our complete rankings for speeds, plans, prices and more. Satellite view of my house, Google earth live Go down from space to street level to explore the entire earth using Google earth street view, a free mapping software. Communications satellite Wikipedia. A communications satellite is an artificial satellite that relays and amplifies radio telecommunications signals via a transponder it creates a communication channel between a source transmitter and a receiver at different locations on Earth. Communications satellites are used for television, telephone, radio, internet, and military applications. There are over 2,0. It is like Google Maps but live. A San Francisco firm has released the first footage from a revolutionary satellite it is set to make available to the public. The. Google Earth for mobile enables you to explore the globe with a swipe of your finger. Fly through 3D cities like London, Tokyo and Rome. Dive in to view the world at. Earths orbit, used by both private and government organizations. 1Wireless communication uses electromagnetic waves to carry signals. These waves require line of sight, and are thus obstructed by the curvature of the Earth. The purpose of communications satellites is to relay the signal around the curve of the Earth allowing communication between widely separated points. 2 Communications satellites use a wide range of radio and microwave frequencies. To avoid signal interference, international organizations have regulations for which frequency ranges or bands certain organizations are allowed to use. This allocation of bands minimizes the risk of signal interference. 3HistoryeditThe concept of the geostationary communications satellite was first proposed by Arthur C. Clarke, building on work by Konstantin Tsiolkovsky. In October 1. 94. Clarke published an article titled Extraterrestrial Relays in the British magazine Wireless World. 4 The article described the fundamentals behind the deployment of artificial satellites in geostationary orbits for the purpose of relaying radio signals. Thus, Arthur C. Clarke is often quoted as being the inventor of the communications satellite and the term Clarke Belt employed as a description of the orbit. 5Decades later a project named Communication Moon Relay was a telecommunication project carried out by the United States Navy. Its objective was to develop a secure and reliable method of wireless communication by using the Moon as a passive reflector and natural communications satellite. The first artificial Earth satellite was Sputnik 1. Put into orbit by the Soviet Union on October 4, 1. MHz. Sputnik 1 was launched as a step in the exploration of space and rocket development. While incredibly important it was not placed in orbit for the purpose of sending data from one point on earth to another. And it was the first artificial satellite in the steps leading to todays satellite communications. The first artificial satellite used solely to further advances in global communications was a balloon named Echo 1. 6 Echo 1 was the worlds first artificial communications satellite capable of relaying signals to other points on Earth. It soared 1,6. 00 kilometres 1,0. Aug. 1. 2, 1. 96. Launched by NASA, Echo 1 was a 3. PET film balloon that served as a passive reflector for radio communications. The worlds first inflatable satellite or satelloon, as they were informally known helped lay the foundation of todays satellite communications. The idea behind a communications satellite is simple Send data up into space and beam it back down to another spot on the globe. Echo 1 accomplished this by essentially serving as an enormous mirror, 1. The first American satellite to relay communications was Project SCORE in 1. It was used to send a Christmas greeting to the world from U. S. President Dwight D. Eisenhower. 7 Courier 1. B, built by Philco, launched in 1. There are two major classes of communications satellites, passive and active. Passive satellites only reflect the signal coming from the source, toward the direction of the receiver. With passive satellites, the reflected signal is not amplified at the satellite, and only a very small amount of the transmitted energy actually reaches the receiver. Since the satellite is so far above Earth, the radio signal is attenuated due to free space path loss, so the signal received on Earth is very, very weak. Active satellites, on the other hand, amplify the received signal before retransmitting it to the receiver on the ground. 3 Passive satellites were the first communications satellites, but are little used now. Telstar was the second active, direct relay communications satellite. Belonging to AT T as part of a multi national agreement between AT T, Bell Telephone Laboratories, NASA, the British General Post Office, and the French National PTT Post Office to develop satellite communications, it was launched by NASA from Cape Canaveral on July 1. Relay 1 was launched on December 1. Pacific Ocean on November 2. An immediate antecedent of the geostationary satellites was the Hughes Aircraft Companys Syncom 2, launched on July 2. Syncom 2 was the first communications satellite in a geosynchronous orbit. It revolved around the earth once per day at constant speed, but because it still had north south motion, special equipment was needed to track it. Its successor, Syncom 3 was the first geostationary communications satellite. Syncom 3 obtained a geosynchronous orbit, without a north south motion, making it appear from the ground as a stationary object in the sky. Beginning with the Mars Exploration Rovers, landers on the surface of Mars have used orbiting spacecraft as communications satellites for relaying their data to Earth. The landers use UHF transmitters to send their data to the orbiters, which then relay the data to Earth using either X band or Ka band frequencies. These higher frequencies, along with more powerful transmitters and larger antennas, permit the orbiters to send the data much faster than the landers could manage transmitting directly to Earth, which conserves valuable time on the NASA Deep Space Network. 9Satellite orbitseditCommunications satellites usually have one of three primary types of orbit, while other orbital classifications are used to further specify orbital details. Geostationary satellites have a geostationary orbit GEO, which is 3. Earths surface. This orbit has the special characteristic that the apparent position of the satellite in the sky when viewed by a ground observer does not change, the satellite appears to stand still in the sky. This is because the satellites orbital period is the same as the rotation rate of the Earth. The advantage of this orbit is that ground antennas do not have to track the satellite across the sky, they can be fixed to point at the location in the sky the satellite appears. Medium Earth orbit MEO satellites are closer to Earth. Orbital altitudes range from 2,0. Earth. The region below medium orbits is referred to as low Earth orbit LEO, and is about 1. Earth. As satellites in MEO and LEO orbit the Earth faster, they do not remain visible in the sky to a fixed point on Earth continually like a geostationary satellite, but appear to a ground observer to cross the sky and set when they go behind the Earth. Therefore, to provide continuous communications capability with these lower orbits requires a larger number of satellites, so one will always be in the sky for transmission of communication signals. However, due to their relatively small distance to the Earth their signals are stronger. clarification neededLow Earth Orbiting LEO satelliteseditA low Earth orbit LEO typically is a circular orbit about 1. Because of their low altitude, these satellites are only visible from within a radius of roughly 1,0. In addition, satellites in low earth orbit change their position relative to the ground position quickly.
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