SATELLITE TECHNOLOGIES. Communications satellites have redefined our world. Satellites and other modern

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1 Amanda Stokes COMM 421 Textbook Paper SATELLITE TECHNOLOGIES Communications satellites have redefined our world. Satellites and other modern telecommunications networks, together with TV, have now altered the patterns and even many of the goals of modern society. Satellites, for better or worse, have made our world global, interconnected, and interdependent (Pelton 3). Our technology possibilities have changed drastically due to the satellite. We can now receive things from all over the world, that we could have never dreamed about before. The links between the financial markets of New York, London, Tokyo, and Hong Kong have created a global stock market. We can pick up a telephone and dial directly to more than seventy countries. In our homes, we can receive dozens of television channels delivered by satellite to cable systems or directly to our backyards. Rooftop antennas link corporate offices, insurance agencies, manufacturing plants, bank branches, and convenience stores (Hudson 1). Satellites have definitely changed the way we live, because without all the technology that it provides we would be lost in a world of chaos. They help us in every way possible to get information where it needs to go and fast. Probably the greatest technological advance that satellites have given is communication between parts of the world that had no way of communicating before. Satellites have been a means of overcoming isolation for people in remote areas around the world, from Alaska and Northern Canada to Brazil, the South Pacific, and the Australian Outback (Hudson 1). Without the invention of the satellite these countries may still not have means of communication to the outside world. Satellites have given us the opportunity to give and receive information from parts of the world that we might have never thought we would communicate with, and in turn this has helped the economy grow. We are now able to buy and sell goods over the phone and the internet that would more or less maybe never have left certain parts of the world. When the satellite first came about communication was very expensive, because information could only be sent through earth stations equipped with tracking devices. Because of low altitude with high orbital velocity, quality of reception was pretty poor. After the passing of the Communication Satellite Act,

2 Hughes Aircraft introduced new satellites with what they called Syncom II and eventually Syncom III. These satellites were geostationary, meaning that they stayed in the same spot in the air. This meant that earth stations didn t need expensive tracking devices anymore. The Syncom 2 and Syncom 3 satellites were the first practical demonstrations of how to launch and operate GEO satellites (Pelton 41). Eventually only three satellites could establish communication service to almost any spot on earth. Intelsat the International Telecommunications Satellite Consortium, used this new kind of service to provide communication throughout the world. As one might already know the first satellite can be associated with Sputnik, created by scientists at the Russian space station. The USSR promised that it would launch a satellite as part of the International Geophysical Year global scientific enterprise, but much of the world felt that it would never happen. They were proved wrong when the successful launch of Sputnik occurred. This caused the United States to want to try and create a satellite of their own. One of the first attempts to do so was by the military. Many attempts made by them failed, but they soon became successful when they launched the Explorer satellite. After the creation of NASA, scientists became even more serious creating new and improved satellites. Many more attempts were made, including the Echo 1 and Echo 2 experiments. These experiments demonstrated that, to be practical and commercially viable, satellite communications would require radio signals to be received, reamplified, and returned to earth with a significant power boost. Otherwise the signals would be too weak and low in capacity to have any practical value (Pelton 38). The Relay satellite and the Telstar satellite launched by NASA in 1962, became the first real display of commercial satellite communications. Communication satellites have many features that make them appropriate for many telecommunications applications. The first being, that geostationary satellites can cover about one-third of the earth s surface. Second since earth stations can be placed anywhere in the satellite s beam the cost of communication is the same whether you are sending information 100 miles or 1,000 miles. The third feature of a communication satellite is that earth stations can be placed wherever they are needed. This means that they do not need to rely on the extension of terrestrial wire, cable, or microwave, meaning earth stations can be installed according to national or organizational priorities regardless of location. Satellites

3 can be very flexible. They allow you to start out at a small capacity, and then add on more or different capacity. Satellite communication is seen as a very reliable kind of communication. Today there have been many advances in the world of satellite communications. We now have services such as satellite TV, Broadband internet satellite, mobile satellite systems, and satellite radio in homes and businesses as well as in the car. These new technologies allow us to receive information more promptly than ever before. They have made our world faster and allow us to be able to do things that otherwise we may never have been able to do. Things such as listen to radio stations from all over the world, receive s from people in different countries, and even have a conversation with someone you may have never thought you would talk to in your life. These satellite technologies have helped our economy and everyday lives prosper for the better. In many ways, direct broadcasting was perhaps the most natural type of service for a truly global medium that is ubiquitous and far reaching as satellites (Pelton 56). Many technology advances had to take place in order for this service to be realized. The first generation of satellites, were too weak to provide direct broadcast services to consumers. This delayed the new Direct to Home (DTH) or Direct Broadcast Satellite (DBS) in getting started. Many obstacles had to be overcome in order for the DBS to become successful. Despite these hurdles, serious efforts to provide direct broadcast satellite TV started in the 1970s on both sides of the Atlantic (Pelton 56). The broadcast technique at that time was analog and required 27 MHz of radio frequency bandwidth for each TV channel, plus extremely high satellite transmission power to reach small receive antennas. This was about 100 times more powerful than the capability needed for ordinary fixed satellite services. This broadcast service would only be able to produce about 5 channels that only covered a medium sized market. Using this type of analog service was not the best option for what they were looking for. Since the analog systems could not compete with the number of channels provided by cable TV systems, some advances needed to be made in the satellite. The first advance made was the change to digital compression. This allowed several TV programs to be squeezed into a single transponder without a lot of impact on subjective reception quality. The second advance was to lower the cost of development and manufacturing. These advances finally made DTH-TV with many more channels possible. It can now provide hundreds of channels right to your home. DTH-TV continues to be in the middle of the ongoing

4 market competition in the satellite and allied industries to become the information hub in every home (Pelton 61). Another advance that has been made in satellite technology is that of satellite digital radio. This technology came about after TV because it was seen as just a way to receive information and entertainment while doing other things as well. In 1997 the FCC gave two slices of the 2.3 GHz S-band spectrum to two companies, XM Radio and Sirius Radio. The XM Radio system uses two operational geostationary satellites simultaneously in space. They also use a variation on a well established Coded Orthogonal Frequency Division Modulation (COFDM)technology. This system has three satellites in the Tundra 24- hour orbit that provide high elevation angles throughout the United States. Sirius Radio also uses a version of COFDM. The XM Radio service is being sold by General Motors, while Sirius is being put into cars made by Ford Motor Company. The subscriber base for this type of satellite system continues to grow everyday, and will continue to grow as long as there are advances in technology. Today there is also another advance in satellite radio. I have seen commercials for a personal satellite radio that goes with you wherever you go. It is called the XM to go. It is kind of like a walkman, but you are able to receive all kinds of stations not just ones that are within reach. It also works as an MP3 player as well. You are able to download songs from the XM satellite as well as from your own collection. There are some downfalls of this particular technology, one being that it cannot hold as many songs as an IPOD. Another is that it is battery powered because it is portable, so you really never know when it is going to lose life. I guess further research will be done on this product, and some things may be changed in the near future. Satellite based internet service is the single most rapidly growing source of revenues for the FSS industry. The largest sector of revenue growth for the past 3 years for Intelsat, Eutelsat, Panamsat, and other FSS systems has been to support backbone Internet distribution services, but these systems have limited ability to provide broadband services directly to consumers (Pelton 65). The real competition in the internet world is that of broadband. The competitive media is DSL, high-speed modems over cable TV systems, satellites, and wireless. DSL and cable modems are probably going to take away most of the market, because they use copper telephone wires and coaxial cables. Cable modems are really being highly attractive options in the United States.

5 Wireless technology is also becoming very popular in the high-speed Internet market. For this technology to continue to grow, it s necessary for it to keep up with the capabilities of broadband terrestrial wireless systems, and satellites. There are still some problems with wireless connection, such as it may only be a good service within a specific area, but soon it will probably be able to be used anywhere. Another technology that has grown from the new uses of satellites is that of mobile satellite systems. The fact that a single satellite can serve as a radio relay to span great distances has supported great improvements in telecommunications-not only for conventional telephone, TV, and data services, but also for ships, aircraft, and mobile travelers all around the world. Developing a mobile satellite service system to serve mobile users and provide key safety and rescue services, while simple in concept, also confronted great technical and operational challenges, as well as a few policy and regulatory issues (Pelton 67). An earth station for a particular vehicle, such as an aircraft or land vehicle has to be on the small side to fit the particular vehicle as well as affordable. From a radio engineer s point of view, this means that the effective radiated power coming down from the mobile satellite in space has to be much stronger than that used to support an FSS channel (Pelton 68). If the mobile system is going to be used while the vehicle is in motion, the earth station antenna has to be nondirectional or omnidirectional, or designed to correctly point at the moving vehicle. When cellular services became popular in the 1980s, cellular companies decided to use satellite systems in order to serve their land mobile users. The communication satellites were seen as the best possible way to provide nationwide and regional-wide coverage for users. One of the popular uses of this technology was for truck fleet management. This way drivers could communicate with there companies while they were on the road. Mobile satellite services are here to stay because the need for ubiquitous communications will always remain. Despite the coverage expansion of terrestrial mobile radio systems, there will always remain areas of the world that will be more economically covered by satellite (Pelton 79). One problem that remains with this technology is reducing the cost of mobile satellite services. Mobile satellite systems that have wide coverage will probably be the future for mobile telephony and internet communication.

6 The future of satellite technology is one that many are waiting for. Many new and important satellite applications have emerged since the 9/11 attacks, as well as from military missions, and natural disasters. These events have given us a reason to explore the capabilities of satellite technology, and invent new and exciting ways to use the satellite. Within a decade, there will likely be satellite-based systems that will use radar, optical imaging, and Micro Electro Mechanical Systems (MEMS) to monitor everything from water supplies to energy plants as a result of antiterrorist concerns (Pelton 318). These satellites will also help us to monitor and control commercial aircraft, as well as warn us of equipment failure. They will also make transportation on the ground and in the sky safer and more efficient. Satellite technology will need to stay on its toes though, in order to compete with the growing technology of fiber optics networks. There are many trends emerging that are driven by satellite and related technologies. Satellites now allow over 200 countries to achieve instant linkage by telephone or internet. User terminals are linked by a combination of broadcast, fixed, navigational, and mobile satellites. Within the next 20 years, satellite user terminals will continue to shrink in size and cost and disappear within our clothing or briefcase or into a hand-held personal data assistant. A flip-down eye loop may even provide us access to live via satellite multimedia information from anywhere on the planet or even outer space colonies (Pelton 343). Wearable satellite terminals and clip on video units seem to be a possible next step for satellite technology. Satellites also have a future in healthcare technology. They allow us to reach even the most remote place with the latest up to date information, about diseases and medical disasters that may be occurring at a particular time. Satellites will enable us to bridge the communication gap that has resided over the world for so many years. Poor countries and developing nations that lack education programs, will now be able receive information that will help them to maybe create better lives for themselves. One can only begin to imagine all the capabilities that satellite technology has given to the world. We are now able to do things that people 100 years ago would never be able to dream of. Often I think we take for granted all of the opportunities we have been given because of the satellite. I guess one could say that or world is starting to be run by technology because it makes things easier for humans. Satellites make things possible and for that we are very grateful.

7 BIBLIOGRAPHY Hudson, Heather E. Communication Satellites: Their Development and Impact. The Free Press, New York pg. 1. Pelton, Joseph N. Communication Satellites: Global Change Agents. Lawrence Erlbaum Associates, Publishers, New Jersey pg. 3,38,41,56,61,65,67,68,79,318,343.