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Satellite communications systems can be divided into two categories: the space and ground segments. The space segment includes satellite and satellite subsystems that are placed in orbit around the earth. The satellite itself consists of several major components, including transponders or channels, a power system (battery modules and solar panels), an antenna system, a command and control system, and satellite housing. The ground segment includes equipment used to receive and/or transmit signals to satellites in orbit and everything from large earth stations used for tracking, telemetry, and control of the satellite to dishes as small as 18 to 24 inches that are used by consumers to receive direct broadcast satellite services.
The United States dominates the world market for large GEO satellites and is among the leaders in the market for the new smaller satellites that will be used in LEO and medium earth orbit (MEO) systems. U.S. industry perceives that U.S. government export controls continue to affect the ability of U.S. companies to enter into joint venture projects overseas. On March 15, 1999, licensing authority for commercial communications satellites was officially transferred from the U.S. Commerce Department’s Bureau of Export Administration to the U.S. State Department’s Office of Defense Trade Controls, as mandated by the National Defense Authorization Act. This shift in authority has resulted in a much more stringent export control regime and has had a significant effect on the ability of U.S. companies to compete for major international projects. As many countries attempt to develop their own satellite manufacturing capabilities, export controls and technology transfer issues are having a significant impact on the ability of U.S. companies to enter into joint ventures with government and private entities in countries such as Russia and China.
A clear trend toward truly global ventures has emerged in the market for smaller satellites for use in LEO and MEO systems. As providers try to find the best technology, the lowest prices, and guaranteed access to markets all over the world, U.S. and foreign companies have formed numerous partnerships. As an increasing number of international ventures are created, it is becoming more difficult to identify precisely the U.S. contribution to many of these ventures. However, the United States is still considered the world leader in the advanced technologies that are critical to the success of these projects.
Despite recent in-orbit satellite malfunctions and the impact of changes in U.S. export control regulations, the United States continues to lead the world in satellite manufacturing. Hughes Space and Communications (Hughes), Lockheed Martin Telecommunications (Lockheed Martin), and Space Systems/Loral (SS/L) are the top three manufacturers of traditional commercial communications satellites built for operation in geostationary orbit. While Hughes, Lockheed Martin, and SS/L remain the key U.S. players in the manufacture of large communications satellites, Boeing, Motorola, Orbital Sciences, Spectrum Astro, and TRW are gaining increased recognition for the manufacture of smaller satellites that will be used for a variety of emerging satellite services.
The global communications market for video, data and voice transmissions is served primarily through terrestrial and submarine optical fiber and coaxial cable, microwave systems and satellites.
Ground-based microwave systems disseminate signals in the form of radio waves from an antenna on top of a building or a transmission tower. Microwave systems are well suited for use by local television stations and cellular telephone systems because the reach of the transmission signal typically is limited to one discrete area. Microwave systems are not suitable for long distance communication or broadcasting, since transmission over long distances requires the construction of a number of microwave relay stations to relay a signal, and repeated transmission can distort a signal. Satellite systems require only two stations to cover long distances, one uplink station and one downlink station. Most importantly, satellites can provide point to multipoint transmissions while simultaneously transmitting signals over the entire region covered within the satellite’s footprint.
Satellite systems generally operate in three main orbits – low-earth orbit (“LEO”), mid-earth orbit (“MEO”) and geostationary orbit (“GEO”). LEO systems operate in orbits at distances of from between just a few hundred miles up to 1,000 miles from earth, whereas MEO systems operate from 1,000 up to 20,000 miles from earth, although they will typically be in the range of 6,000 to 15,000 miles high. Satellites in these systems are not geostationary, that is, they do not constantly overlook the same area on earth. The inability to cover the same area on earth continuously makes these systems impractical for broadcasting and traditional telecommunications usage. In general, LEO and MEO systems comprise of a series of satellites that are used commercially primarily for mobile satellite services. By contrast, GEO satellites are located in orbit approximately 22,300 miles above earth and can blanket large geographic areas with signal coverage.
GEO satellites can be accessed through an uplink station virtually anywhere within the satellite’s footprint. With broad coverage capability, GEO satellites have commonly been used for (i) television broadcasting, principally to cable operators for redistribution and also to households equipped with direct reception antennae as well as for supplementary terrestrial transmission networks in remote areas, (ii) international and domestic trunk telephony omplementing optical fiber and coaxial cable and microwave backbone networks and (iii) business services, principally for voice, data and video transmissions to private networks such as VSAT networks and program exchanges between television broadcasters, including satellite news gathering.
Communications satellites typically are evaluated on (i) their coverage area or “footprint”, (ii) the quality of the signal transmitted to the coverage area and (iii) the availability of the transponders. Footprint is a measurement of the breadth of a satellite’s coverage. A key measurement of signal quality is the intensity of transmission power in the coverage area. Higher power signal enables a customer to use smaller, lower-cost antennae on the ground. Availability is determined by considering a satellite’s operational “lifetime” as well as the number of transponders capable of providing service. The Company considers all three factors in determining whether a particular satellite is appropriate for its needs.
Commercial telecommunications and broadcast satellites typically transmit signals using either C-band or Ku-band. C-band is used worldwide for satellite communications to transmit signals with less interference from atmospheric conditions. C-band frequencies are also used by ground-based microwave systems. In certain parts of the world, C-band satellite transmission antennae must be located far from centers of population to avoid interference with ground-based systems. Since there are fewer Ku-band systems in existence than C-band systems, more powerful Ku-band transponders can be used in urban areas without similar interference concerns. Because of higher available transmission power, Ku-band frequencies can be used in conjunction with antennae that are smaller than antennae that are used in conjunction with C-band frequencies. Ku-band is generally used for the same purposes as C-band as well as for satellite news-gathering (transportable antennae) and in some VSAT applications.
The combination of high power transmitters and small antennae also makes Ku-band suitable for direct-to-home television.
Direct-to-home television did not become commercially viable until recently because available satellite technology did not have the power to transmit to receivers and digital compression technology had not been adequately developed. Today, DBS provides an efficient point-to-multipoint delivery of video and audio transmissions. The advent of high-powered satellites allows for dishes as small as 18 inches and digital compression technology permits the broadcast of up to 10 channels of programming per transponder. In the United States, Europe and Japan, DBS operators have had success in penetrating their respective markets.
Satellite operators such as APT provide satellite transponder capacity. For television programming distribution, these services may consist of arranging satellite capacity and providing teleport transmission facilities and other value-added services. Services for other broadcasting applications, such as live news and sports reporting, may include the arrangement of satellite capacity, the provision of trucks equipped for live news and sports broadcasts, transmission scheduling and signal monitoring. Services for business communications networks are generally more extensive and may include arranging satellite capacity, procurement and installation of on-site antennae and network design, integration, management, operation and maintenance. Satellite operators either provide these services or provide satellite capacity to other companies which provide these services. The Company has chosen to focus on the provision of satellite transponder capacity, through the establishment of the APSTAR System, in order to maximize the efficient use of its resources so as to provide the highest quality service.
Technological advances will increase information carrying capacity and reduce transmission and equipment costs which may, in turn, stimulate demand for satellite communications services. Such advances include the following:
High-powered Satellites. New satellites, which are of higher power, can deliver improved quality signals to antennae that are generally smaller and less expensive (and are therefore more convenient for private and commercial use) and can cover a larger area than those used with earlier-generation satellites. The increasing use of these smaller, less expensive antennae is expanding the markets for public and private communications networks and video distribution services.
Digital Communications. Analog telephone systems carry relatively low volumes of information. Globally, telephone companies are rebuilding their infrastructure to carry high-speed digital communications, which permit new and enhanced business communications and consumer services. Examples include video phones, video conferencing, video-on-demand, wide-area networks, telecommuting and interactive TV. Many of these services use satellite transponder capacity within their transmission circuits and, because of their high transmission rates, will require significant transponder capacity. Furthermore, developments in digital technology for VSATs, which reduce terminal size and increase transmission throughput, are encouraging the development of new, cost-effective business and rural communications applications.
Compressed Digital Video. Digital video compression technology is designed to compress multiple high-quality video channels into the same transponder capacity that previously carried one analog channel. This technology facilitates a significant increase in the number of available video channels with improved transmission quality and allows satellite operators to provide satellite transmission services using less bandwidth. Digital video compression technology is expected to lower the costs of delivering programming via satellite and cable television systems, thereby permitting more programming options to be provided to niche markets. Digital video compression technology may also permit broadcasters, by lowering per channel costs, to offer local broadcasting platforms including programming designed for particular national audiences and particular cultures and languages. The Company believes that digital video compression technology may facilitate the efforts of broadcasters to distribute their programming regionally to multiple audiences.
Digital video compression technology may also in the future facilitate the introduction of HDTV. Digital video compression technology is expected to permit HDTV signal with superior picture quality to use an amount of bandwidth comparable to that used by a current analog channel with a far inferior image since analog form typically consumes large amounts of bandwidth.
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