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satellite communication pdf report - vijay123 - 10-04-2017 [attachment=3649] ADVANCEMENTS IN SATELLITE COMMUNICATION Presented By: ASHISH JAIN SRINIVAS.K E.C.E (II/IV). RAGHU ENGG.COLLEGE. ANDHRA PRADESH. ABSTRACT: Satellites have evolutionized communication. Satellite communication has served mankind in many ways for instance its is used to predict weather and broadcast storm warnings and also provides a wide range of communication services in the fields of relaying television programs, digital data for a multitude of business services. It might not surprise us if, in near future satellite links are used for voice and fax transmission to aircraft on international routes. Communications satellite systems have entered a period of transition from point-to-point high-capacity trunk communications between large, costly ground terminals to multipoint-to-multipoint communications between small, low-cost stations. As any invention develops with the passage of time, satellite communication has also moved a step ahead from what it was in the past with the use of several techniques such as frequency reuse, interconnecting many ground stations spread over the world, concept of multiple spot beam communications, these days lasers are effectively used for transmission through satellites. The latest development in satellites is the use of networks of small satellites in low earth orbits. In this present era, communication plays a vital role. We use a wide range of devices to communicate between two persons placed at different places (irrespective of the distance between them). Any earth-orbiting spacecraft that provides communication over long distances by reflecting or relaying radio-frequency signals. Satellites have evolutionized communication by making worldwide telephone links and live broadcasts common occurrences. A satellite receives a microwave signal from a ground station on the earth (the uplink), then amplifies and retransmits the signal back to a receiving station or stations on earth at a different frequency (the downlink). A communication satellite is in geosynchronous orbit, which means that it is orbiting at the same speed as the earth is revolving. The satellite stays in the same position relative to the surface of the earth, so that the broadcasting station will never lose contact with the receiver. DEVELOPMENT IN SATELLITE COMMUNICATION: Some of the first communications satellites were designed to operate in a passive mode. Instead of actively transmitting radio signals, they served merely to reflect signals that were beamed up to them by transmitting stations on the ground. Signals were reflected in all directions, so receiving stations around the world could pick them up. Echo 1, launched by the United States in 1960, consisted of an aluminized plastic balloon 30 m (100 ft) in diameter. Launched in 1964, Echo 2 was 41 m (135 ft) in diameter. The capacity of such systems was severely limited by the need for powerful transmitters and large ground antennas. Score, launched by the United States in 1958, was the first active communications satellite. It was equipped with a tape recorder that stored messages received while passing over a transmitting ground station. These messages were retransmitted when the satellite passed over a receiving station. Telstar 1, launched by American Telephone and Telegraph Company in 1962, provided direct television transmission between the United States, Europe, and Japan and could also relay several hundred-voice channels. Launched into an elliptical orbit inclined 45 to the equatorial plane, Telstar could only relay signals between two ground stations for a short period during each revolution, when both stations were in its line of sight. Hundreds of active communications satellites are now in orbit. They receive signals from one ground station, amplify them, and then retransmit them at a different frequency to another station. Satellites use ranges of different frequencies, measured in hertz (Hz) or cycles per second, for receiving and transmitting signals. Many satellites use a band of frequencies of about 6 billion hertz, or 6 gigahertz (GHz) for upward, or uplink, transmission and 4 GHZ for downward, or downlink, transmission. Another band at 14 GHZ (uplink) and 11 or 12 GHZ (downlink) is also much in use, mostly with fixed (nonmobile) ground stations. A band at about 1.5 GHZ (for both uplink and downlink) is used with small, mobile ground stations (ships, land vehicles, and aircraft). Solar energy cells mounted on large panels attached to the satellite provide power for reception and transmission. GEOSYNCHRONOUS ORBIT: A satellite in a geosynchronous orbit follows a circular orbit over the equator at an altitude of 35,800 km (22,300 mi), completing one orbit every 24 hours, in the time that it takes the earth to rotate once. Moving in the same direction as the earth's rotation, the satellite remains in a fixed position over a point on the equator, thereby providing uninterrupted contact between ground stations in its line of sight. The first communications satellite to be placed in this type of orbit was Syncom 2, launched by the National Aeronautics and Space Administration (NASA) in 1963. Most communications satellites that followed were also placed in geosynchronous orbit. COMMERCIAL COMMUNICATIONS SATELLITES: Deployment and operation of communications satellites on a commercial basis began with the founding of the Communications Satellite Corporation (COMSAT) in 1963. When the International Telecommunications Satellite Organization (INTELSAT) was formed in 1964, COMSAT became the U.S. member. Based in Washington, D.C., INTELSAT is owned by more than 120 nations. Intelsat 1, known as Early Bird, launched in 1965, provided either 240 voice circuits or one two-way television channel between the United States and Europe. During the 1960s and 1970s, message capacity and transmission power of the Intelsat 2, 3, and 4 generations were progressively increased. The first of the Intelsat 4s, launched in 1971, provided 4,000 voice circuits. With the Intelsat 5 series (1980), innovations in signal focusing resulted in additional increases in capacity. A satellite's power could now be concentrated on small regions of the earth, making possible smaller-aperture, lower-cost ground stations. An Intelsat 5 satellite can typically carry 12,000 voice circits. The Intelsat 6 satellites, which entered service in 1989, can carry 24,000 circuits and feature dynamic on-board switching of telephone capacity among six beams, using a technique called SS-TDMA (satellite-switched time division multiple access). In the early 2000s, INTELSAT had 21 satellites in orbit, providing the world's most extensive telecommunications system. Other systems also provide international service in competition with INTELSAT. The growth of international systems has been paralleled by domestic and regional systems, such as the U.S. Telstar, Galaxy, and Spacenet programs and Europe's Eutelsat and Telecom. SERVICES: Broadcasters use data from meteorological satellites to predict weather and to broadcast storm warnings when necessary. Satellites such as the Geostationary Operational Environmental Satellite (GOES) collect meteorological and infrared information about the atmosphere and the ocean. A camera on the GOES is continuously pointed at Earth, broadcasting satellite images of cloud patterns both day and night. Here, the GOES-C satellite is being encapsulated inside its payload fairing aboard a Delta rocket. Commercial satellites provide a wide range of communications services. Television programs are relayed internationally, giving rise to the phenomenon known as the "global village." Satellites also relay programs to cable television systems as well as to homes equipped with dish antennas. In addition, very small aperture terminals (VSATs) relay digital data for a multitude of business services. Intelsat satellites now carry over 100,000 telephone circuits, with growing use of digital transmission. Digital source coding methods have resulted in a ten-fold reduction in the transmission rate needed to carry a voice channel, thus enhancing the capacity of existing facilities and reducing the size of ground stations that provide telephone service. Weather satellites carry cameras and other instruments pointed toward Earth's atmosphere. They can provide advance warning of severe weather and are a great aid to weather forecasting. NASA launched the first weather satellite, Television Infrared Observation Satellite (TIROS) 1, in 1960. TIROS 1 transmitted almost 23,000 photographs of Earth and its atmosphere. NASA operates the Geostationary Operational Environmental Satellite (GOES) series, which are in geostationary orbit. GOES provides information for weather forecasting, including the tracking of storms. Meteosat 3, a European weather satellite also in geostationary orbit, augments GOES. The National Oceanic and Atmospheric Administration (NOAA) operate three satellites that collect data for long-term weather forecasting. The International Mobile Satellite Organization (INMARSAT), founded in 1979 as the International Maritime Satellite Organization, is a mobile telecommunications network, providing digital data links, telephone, and facsimile transmission, or fax, service between ships, offshore facilities, and shore-based stations throughout the world. It is also now extending satellite links for voice and fax transmission to aircraft on international routes. RECENT TECHNICAL ADVANCES: Launched on October 4, 1957, the Sputnik 1 was the first craft in Earth's orbit. Named after the Russian word for "traveling companion of the world" (Sputnik Zemli), it was a small satellite measuring only 58 cm (23 in) across. It circled the earth once every 96.2 minutes and transmitted atmospheric information by radio. After three months aloft, it was destroyed while reentering the atmosphere. Communications satellite systems have entered a period of transition from point-to-point high-capacity trunk communications between large, costly ground terminals to multipoint-to-multipoint communications between small, low-cost stations. The development of multiple access methods has both hastened and facilitated this transition. With TDMA, each ground station is assigned a time slot on the same channel for use in transmitting its communications; all other stations monitor these slots and select the communications directed to them. By amplifying a single carrier frequency in each satellite repeater, TDMA ensures the most efficient use of the satellite's onboard power supply. A technique called frequency reuse allows satellites to communicate with a number of ground stations using the same frequency by transmitting in narrow beams pointed toward each of the stations. Beam widths can be adjusted to cover areas as large as the entire United States or as small as a state like Maryland. Two stations far enough apart can receive different messages transmitted on the same frequency. Satellite antennas have been designed to transmit several beams in different directions, using the same reflector. A method for interconnecting many ground stations spread over great distances was demonstrated in 1993 with the launch of NASA's ACTS (Advanced Communications Technology Satellite). The satellite uses what is known as the hopping spot beam technique to combine the advantages of frequency reuse, spot beams, and TDMA. By concentrating the energy of the satellite's transmitted signal, ACTS can use ground stations that have smaller antennas and reduced power requirements. The concept of multiple spot beam communications was successfully demonstrated in 1991 with the launch of Italsat, developed by the Italian Research Council. With six spot beams operating at 30 GHZ (uplink) and 20 GHZ (downlink), the satellite interconnects TDMA transmissions between ground stations in all the major economic centers of Italy. It does this by demodulating uplink signals, routing them between up- and downlink beams, and combining and remodulating them for downlink transmission. Laser beams can also be used to transmit signals between a satellite and the earth, but the rate of transmission is limited because of absorption and scattering by the atmosphere. Lasers operating in the blue-green wavelength, which penetrates water, have been used for communication between satellites and submarines. The latest development in satellites is the use of networks of small satellites in low earth orbit (2,000 km (1,200 mi) or less) to provide global telephone communication. The Iridium system uses 66 satellites in low earth orbit, while other groups have or are developing similar systems. Special telephones that communicate with these satellites allow users to access the regular telephone network and place calls from anywhere on the globe. Anticipated customers of these systems include international business travelers and people living or working in remote areas. CONCLUSION: Looking at the rate of advancement in satellite communication one would foresee the use of satellites in every field where communication is required such as relaying television and radio signals. Special telephones that communicate with these satellites allow users to access the regular telephone network and place calls from anywhere on the globe. REFERENCES: WEBSITES: > encarta.msn.commsn.encarta.com > amazon.com > electronicsforu.com ARTICLES: > Communication satellites > Wireless communications > Artificial satellites > Space exploration. BOOKS: > Satellite Communications by Timothy Pratt and Dennis Roddy. > Satellite Communication Systems by M. Richharia. > Satellite communication systems by Gerard Maral, Michel Bousquet read more http://ocw.mit.edu/NR/rdonlyres/Aeronautics-and-Astronautics/16-851Fall2003/D74258BE-1FED-4676-988C-AC13D07EC899/0/l21satelitecomm2_done.pdf http://odyseus.nildram.co.uk/Systems_And_Devices_Files/Sat_Comms.pdf http://cse.wustl.edu/ jain/cis788-97/ftp/satellite_nets.pdf satellite communication pdf report - nadeem - 10-04-2017 [attachment=3778] PRESENTED BY A.N.SIREESHA, II-B.TECH,ECE. & C.SOWJANYA, II-B.TECH,ECE. SRI VENKATESWARA COLLEGE OF ENGINEERING AN TECHNOLOGY,R.V.S NAGAR,CHITTOOR,517002. CONTENTS What is a satellite Can we imitate nature(artificial satellites) Types of satellites. Why satellites for communication Low earth-orbiting communication satellites. Geosynchronous communication satellite. Basic communication satellite components How satellites are used today. New satellite communications. The note book computer :the latest in satellite gear. Direct broadcast: Satellite T.V. Satellite advances in television. Future global satellite network. Some of the launch vehicles used to send satellites into space. Conclusion & Bibliography. ABSRACT The main theme involved in developing this paper is to provide a clear understanding of satellites,pupose of satellites and their types, need of satellite communications in day-to-day life. there are two types of communication satellites low earth orbit communication satellites (LEO) and geosynchronous communication satellites. under LEO communication satellites there comes Echo and Telstar communication satellites, their advantages and disadvantages and advancements of geosynchronous communication satellites compared to LEO s has been discussed. A brief idea on basic communication satellite components has been given. In the years to come, there are many projected plans in the area of satellites. This will be a benefit to the United States and the rest of the world. Some of these advances are in satellite photography, communications, and weather technology. Some of the future advances are in the distant future, while others are being developed right now. The usage of satellites today, new satellite communications, the latest in satellite gear, direct broadcast satellite T.V, satellite advances in television, future global satellite networks. we have also presented some of the launch vehicles used to send satellites into space. What is a Satellite A satellite is something that goes around and around a larger something, like the earth or another planet. Some satellites are natural, like the moon, which is a natural satellite of the earth. Other satellites are made by scientists and technologists to go around the earth and do certain jobs. Can We Imitate Nature (Artificial Satellites) Very soon after Newton's laws were published, people realized that in principle it should be possible to launch an artificial satellite which would orbit the earth just as the moon does. A simple calculation, however, using the equations which we developed above, will show that an artificial satellite, orbiting near the surface of the earth (R = 4000 miles) will have a period of approximately 90 minutes. This corresponds to a sideways velocity (needed in order to "miss" the earth as it falls), of approximately 17,000 miles/hour (that's about 5 miles/second). Types Of Satellites Boeing 376, built by Boeing Satellite Systems. The Boeing 376 is used mostly for broadcast television and cable television. Boeing 601 which is also built by Boeing Satellite Systems. The Boeing 601 is used for many purposes, including direct broadcast TV, such as DIRECTV. Direct broadcast TV is a system for receiving television using a very small satellite dish. The television signal is relayed by a Boeing 601 satellite. The Boeing 601 also relays telephone, fax, and computer communications. The most powerful commercial satellite in the world is the Boeing 702. Designed and built by Boeing Satellite Systems, this giant has a wingspan of nearly 157 feet more than a Boeing 757 jet plane. Why Satellites for Communications By the end of World War II, the world had had a taste of "global communications." Edward R. Murrow's radio broadcasts from London had electrified American listeners. We had, of course, been able to do transatlantic telephone calls and telegraph via underwater cables for almost 50 years. At exactly this time, however, a new phenomenon was born. The first television programs were being broadcast, but the greater amount of information required to transmit television pictures required that they operate at much higher frequencies than radio stations. Television signals, however required much higher frequencies because they were transmitting much more information - namely the picture. Both radio and television frequency signals can propagate directly from transmitter to receiver. This is a very dependable signal, but it is more or less limited to line of sight communication. T0he mode of propagation employed for long distance (1000s of miles) radio communication was a signal which traveled by bouncing off the charged layers of the atmosphere (ionosphere) and returning to earth. The higher frequency television signals did not bounce off the ionosphere and as a result disappeared into space in a relatively short distance. This is shown in the diagram below. Radio Signals Reflect Off the Ionosphere; TV Signals Do Not In addition, of course, the appetite for transatlantic radio and telephone was increasing rapidly. Adding this increase to the demands of the new television medium, existing communications capabilities were simply not able to handle all of the requirements. By the late 1950s the newly developed artificial satellites seemed to offer the potential for satisfying many of these needs. Low Earth-Orbiting Communications Satellites In 1960, the simplest communications satellite ever conceived was launched. It was called Echo, because it consisted only of a large (100 feet in diameter) aluminized plastic balloon. Radio and TV signals transmitted to the satellite would be reflected back to earth and could be received by any station within view of the satellite. Echo Satellite Unfortunately, in its low earth orbit, the Echo satellite circled the earth every ninety minutes. This meant that although virtually everybody on earth would eventually see it, no one person, ever saw it for more than 10 minutes or so out of every 90 minute orbit. In 1958, the Score satellite had been put into orbit. It carried a tape recorder which would record messages as it passed over an originating station and then rebroadcast them as it passed over the destination. Once more, however, it appeared only briefly every 90 minutes - a serious impediment to real communications. In 1962, NASA launched the Telstar satellite for AT&T. Telstar Communications Satellite Telstar's orbit was such that it could "see" Europe" and the US simultaneously during one part of its orbit. During another part of its orbit it could see both Japan and the U.S. As a result, it provided real- time communications between the United States and those two areas - for a few minutes out of every hour. Geosynchronous Communications Satellites: The solution to the problem of availability, of course, lay in the use of the geosynchronous orbit. In 1963, the necessary rocket booster power was available for the first time and the first geosynchronous satellite , Syncom 2, was launched by NASA. For those who could "see" it, the satellite was available 100% of the time, 24 hours a day. The satellite could view approximately 42% of the earth. For those outside of that viewing area, of course, the satellite was NEVER available. Syncom II Communications Satellite However, a system of three such satellites, with the ability to relay messages from one to the other could interconnect virtually all of the earth except the polar regions. The one disadvantage (for some purposes) of the geosynchronous orbit is that the time to transmit a signal from earth to the satellite and back is approximately of a second - the time required to travel 22,000 miles up and 22,000 miles back down at the speed of light. For telephone conversations, this delay can sometimes be annoying. For data transmission and most other uses it is not significant. In any event, once Syncom had demonstrated the technology necessary to launch a geosynchronous satellite, a virtual explosion of such satellites followed. Today, there are approximately 150 communications satellites in orbit, with over 100 in geosynchronous orbit. One of the biggest sponsors of satellite development was Intelsat, an internationally-owned corporation which has launched 8 different series of satellites (4 or 5 of each series) over a period of more than 30 years. Spreading their satellites around the globe and making provision to relay from one satellite to another, they made it possible to transmit 1000s of phone calls between almost any two points on the earth. It was also possible for the first time, due to the large capacity of the satellites, to transmit live television pictures between virtually any two points on earth. By 1964 (if you could stay up late enough), you could for the first time watch the Olympic games live from Tokyo. A few years later of course you could watch the Vietnam war live on the evening news. Basic Communications Satellite Components Every communications satellite in its simplest form (whether low earth or geosynchronous) involves the transmission of information from an originating ground station to the satellite (the uplink), followed by a retransmission of the information from the satellite back to the ground (the downlink). The downlink may either be to a select number of ground stations or it may be broadcast to everyone in a large area. Hence the satellite must have a receiver and a receive antenna, a transmitter and a transmit antenna, some method for connecting the uplink to the downlink for retransmission, and prime electrical power to run all of the electronics. The exact nature of these components will differ, depending on the orbit and the system architecture, but every communications satellite must have these basic components. This is illustrated in the following drawing. Basic Components of a Communications Satellite Link How Satellites are Used Today Today Satellites are used for direct broadcast television, wireless cable, cellular telephone, photography, and video tele-conferencing. The special sports programs, movies, and news broadcasts are all televised because of satellites. Artificial satellites have been launched to photograph the moon, Mars, Venus, Saturn, and Jupiter. Other satellites send information, back to the Earth about the weather of the Earth. Planet 1: New Satellite Communications A new satellite system is known as Planet 1. It integrates cellular and satellite technology to provide mobile voice, data, and facsimile communications. "The package weighs less than six pounds and the price is $2,995, plus a $3 a minute in use charges." (Miller, 134) By the end of the year, it is expected that Planet 1 service will be offered to countries all around the world. The Notebook Computer: The Latest in Satellite Gear Now the business traveler can go anywhere on business without having to worry whether they can make their business call. New technology has put the out of touch traveler in touch with the world. Recent advances in satellite technology have provided the use of compact cellular phones. "Travelers can take along the latest in satellite gear, which is no bigger than a notebook computer."(Miller,134) Direct Broadcast: Satellite TV Direct Broadcast Satellite television is a very costly business. Wireless cable technology brings pay TV to rural areas. This technology works by beaming signals from a central tower to dishes on the roofs of houses or buildings. The new technology is cheaper than laying wires under the ground. Satellite Advances in Television Special satellites send pictures and messages from one continent to another . Dish antennas are used to send and receive information. A television show that is broadcasted live from one country can also be seen in another country which is half way around the world. Communication services are now using small antennas to send and receive the information. Future Global Satellite Network AT&T Corp. has filed an application to build and launch a global satellite network. This would allow computer users to bypass telephone networks and connect directly to the internet by satellite. "AT&T has used satellites in its international long distance network." (Ley,32) This new technology would involve a network of satellites positioned around the Earth. Some of the launch vehicles used to send satellites into space CONCLUSION: Additional satellites are scheduled for launch that will enable new communication systems to be used around the world. Advances in the new Satellite Technology have made people no more than a phone call away. Satellites can send messages from one continent to another and also from one planet to another. Satellite technology brings us the weather, cellular phones, wireless cable, and direct broadcast television. Satellite communication companies are expecting these services to be offered all over the world in the very near future. BIBLOGRAPHY: connected-earth.com. boeing.com technology-post.com info.com satellite communication pdf report - prafful_1988 - 10-04-2017 satellite communication [attachment=16768] History See: Geostationary Orbit and Geosynchronous orbit Satellites. The first artificial satellite was the Soviet Sputnik 1, launched on October 4, 1957, and equipped with an on-board radio-transmitter that worked on two frequencies, 20.005 and 40.002 MHz. The first American satellite to relay communications was Project SCORE in 1958, which used a tape recorder to store and forward voice messages. It was used to send a Christmas greeting to the world from U.S. President Dwight D. Eisenhower. NASA launched an Echo satellite in 1960; the 100-foot (30 m) aluminized PET film balloon served as a passive reflector for radio Molniya satellites Main article: Molniya orbit Geostationary satellites must operate above the equator and will therefore appear lower on the horizon as the receiver gets the farther from the equator. This will cause problems for extreme northerly latitudes, affecting connectivity and causing multipath (interference caused by signals reflecting off the ground and into the ground antenna). For areas close to the North (and South) Pole, a geostationary satellite may appear below the horizon. Therefore Molniya orbit satellite have been launched, mainly in Russia, to alleviate this problem. Satellite Applications The first and historically most important application for communication satellites was in intercontinental long distance telephony. The fixed Public Switched Telephone Network relays telephone calls from land line telephones to an earth station, where they are then transmitted to a geostationary satellite. The downlink follows an analogous path. Improvements in submarine communications cables, through the use of fiber-optics, caused some decline in the use of satellites for fixed telephony in the late 20th century, but they still serve remote islands such as Ascension Island, Saint Helena, Diego Garcia, and Easter Island, where no submarine cables are in service. There are also regions of some continents and countries where landline Fixed Service Satellite Fixed Service Satellites use the C band, and the lower portions of the Ku bands. They are normally used for broadcast feeds to and from television networks and local affiliate stations (such as program feeds for network and syndicated programming, live shots, and backhauls), as well as being used for distance learning by schools and universities, business television (BTV), Videoconferencing, and general commercial telecommunications. FSS satellites are also used to distribute national cable channels to cable television headends. satellite communication pdf report - rejinraj - 10-04-2017 Satellite Communications [attachment=18081] Basics: Advantages of Satellites The advantages of satellite communication over terrestrial communication are: The coverage area of a satellite greatly exceeds that of a terrestrial system. Transmission cost of a satellite is independent of the distance from the center of the coverage area. Satellite to Satellite communication is very precise. Higher Bandwidths are available for use. Basics: Factors in satellite communication Elevation Angle: The angle of the horizontal of the earth surface to the center line of the satellite transmission beam. This effects the satellites coverage area. Ideally, you want a elevation angle of 0 degrees, so the transmission beam reaches the horizon visible to the satellite in all directions. However, because of environmental factors like objects blocking the transmission, atmospheric attenuation, and the earth electrical background noise, there is a minimum elevation angle of earth stations. Basics: How Satellites are used Service Types Fixed Service Satellites (FSS) Example: Point to Point Communication Broadcast Service Satellites (BSS) Example: Satellite Television/Radio Also called Direct Broadcast Service (DBS). Mobile Service Satellites (MSS) Example: Satellite Phones Geostationary Earth Orbit (GEO) These satellites are in orbit 35,863 km above the earth s surface along the equator. Objects in Geostationary orbit revolve around the earth at the same speed as the earth rotates. This means GEO satellites remain in the same position relative to the surface of earth. LEO Disadvantages A network of LEO satellites is needed, which can be costly LEO satellites have to compensate for Doppler shifts cause by their relative movement. Atmospheric drag effects LEO satellites, causing gradual orbital deterioration. MEO Advantage A MEO satellite s longer duration of visibility and wider footprint means fewer satellites are needed in a MEO network than a LEO network. Disadvantage A MEO satellite s distance gives it a longer time delay and weaker signal than a LEO satellite, though not as bad as a GEO satellite. satellite communication pdf report - ash_mech - 10-04-2017 to get information about the topic future satellite communication full report ,ppt and related topic refer the page link bellow http://seminarsprojects.net/Thread-trends-in-satellite-communications-and-the-role-of-optical-free-space-communications http://seminarsprojects.net/Thread-optical-satellite-communication-download-full-report-and-abstract http://seminarsprojects.net/Thread-optical-satellite-communication-seminars-report http://seminarsprojects.net/Thread-satellite-communication-full-report?pid=40617#pid40617 http://seminarsprojects.net/Thread-mobile-satellite-communication-full-report http://seminarsprojects.net/Thread-satellite-communication-full-report http://seminarsprojects.net/Thread-future-satellite-communication--5509 http://seminarsprojects.net/Thread-future-satellite-communication http://seminarsprojects.net/Thread-satellite-communication-pdf-report http://seminarsprojects.net/Thread-future-satellite-communication--5509?page=3 satellite communication pdf report - japandalal - 10-04-2017 to get information about the topic future satellite communication full report ,ppt and related topic refer the page link bellow http://seminarsprojects.net/Thread-trends-in-satellite-communications-and-the-role-of-optical-free-space-communications http://seminarsprojects.net/Thread-optical-satellite-communication-download-full-report-and-abstract http://seminarsprojects.net/Thread-optical-satellite-communication-seminars-report http://seminarsprojects.net/Thread-satellite-communication-full-report?pid=40617#pid40617 http://seminarsprojects.net/Thread-mobile-satellite-communication-full-report http://seminarsprojects.net/Thread-satellite-communication-full-report http://seminarsprojects.net/Thread-future-satellite-communication--5509 http://seminarsprojects.net/Thread-future-satellite-communication http://seminarsprojects.net/Thread-satellite-communication-pdf-report http://seminarsprojects.net/Thread-future-satellite-communication--5509?page=3 satellite communication pdf report - abhijith - 10-04-2017 to get information about the topic DESIGN OF EARTH STATION FOR THE SATELLITE COMMUNICATION full report ppt and related topic refer the page link bellow http://seminarsprojects.net/Thread-optical-satellite-communication-seminars-report http://seminarsprojects.net/Thread-mobile-satellite-communication-full-report http://seminarsprojects.net/Thread-satellite-communication-full-report?mode=linear http://seminarsprojects.net/Thread-satellite-communication-pdf-report http://seminarsprojects.net/Thread-satellite-communication-full-report?mode=linear http://seminarsprojects.net/Thread-future-satellite-communication--5509?page=3 http://seminarsprojects.net/Thread-satellite-communication-systems http://seminarsprojects.in/attachment.php?aid=1721 http://seminarsprojects.net/Thread-optical-satellite-communication-download-full-report-and-abstract http://seminarsprojects.net/Thread-satellite-communications-an-overview satellite communication pdf report - abhi_rulz - 10-04-2017 to get information about the topic Two radar satellite communications full report ,ppt and related topic refer the page link bellow http://seminarsprojects.net/Thread-optical-satellite-communication-seminars-report http://seminarsprojects.net/Thread-satellite-communication-pdf-report http://seminarsprojects.net/Thread-future-satellite-communication--5509 |