Digital Satellite Communication By Tri T Ha Pdf Free Download
Oludare Padilla
Digital Satellite System is the initialism expansion of the DSS digital satellite television transmission system used by DirecTV. Only when digital transmission was introduced did direct broadcast satellite (DBS) television become popular in North America, which has led to both DBS and DSS being used interchangeably to refer to all three commonplace digital transmission formats; DSS, DVB-S and 4DTV. Analog DBS services, however, existed prior to DirecTV and were still operational in continental Europe until April 2012.[1]
DirecTV is now using a modified version of DVB-S2, the latest version of the DVB-S protocol, for HDTV services off the SPACEWAY-1, SPACEWAY-2, DirecTV-10 and DirecTV-11[2] satellites; however, huge numbers of DSS encoded channels still remain. The ACM modulation scheme used by DirecTV prevents regular DVB-S2 demodulators from receiving the signal although the data carried are regular MPEG-4 transport streams.
Satellite communication plays roles in even more critical scenarios around the world. It helped to keep Ukrainian refugees in contact with loved ones after being displaced by war, and it powered disaster response and business recovery after Hurricane Harvey.
Satellite communication service works by leveraging artificial satellites to create communication links between different points on Earth. Positioned in various orbits, satellites receive and transmit signals, ensuring continuous connectivity to serve a variety of important applications.
Satellite communication service offers more flexible, scalable, and wide-reaching internet connectivity than any other internet connectivity methods or providers. Here are some of the most important benefits it providers to customers:
Unlike traditional land-based networks that can be susceptible to natural disasters or infrastructural failures, satellites offer more resilient connectivity solutions. This ensures that users have a dependable communication channel even during unexpected challenges or events.
Additionally, with advancements in technology, satellite systems can be quickly reconfigured or augmented to address changing user needs or to integrate with other evolving technologies, ensuring they remain relevant and efficient in dynamic environments.
One of the standout features of satellite communication is its ability to provide seamless connectivity for moving vessels. Ships, airplanes, and automobiles can all use satellite internet to stay connected while moving, allowing for everything from in-flight streaming entertainment, GPS navigation, easier personal communication while traveling, and better defense communication.
In sectors like defense, where real-time and consistent communication can be the difference between mission success or failure, satellite services are indispensable by helping facilitate mission-critical decisions.
The role of satellite communication service in powering global connectivity is undeniable. In the future, as satellite technologies and innovations continue to advance, this role will only intensify. From delivering the convenience of connectivity on-the-go, to enhancing digital inclusion and equity, to providing reliable connectivity in disaster recovery, satellite internet has become indispensable in our modern world.
This document provides an outline for a course on digital satellite communications. It begins with course objectives, then provides an introduction to satellite communication principles. The basics section explains how satellite communication works, including earth station components and signal transmission. It also covers satellite types like GEO, LEO and MEO, as well as factors that impair signals. The document discusses frequency bands, network configurations, capacity allocation methods, and applications of satellite technology. Overall it aims to give students an overview of digital satellite communication systems and components.Read less
Satellite communication systems have now essentially become extremely high throughput software-defined radios (SDRs) coupled with Advanced Antenna Systems (AAS) that use new technologies to deliver the most flexible and highest performance communication link to as many consumers as possible. To meet these requirements a satellite communication payload that may have once consisted of a multitude of analog components, is now built with DACs, ADCS, FPGAs, ASICs, DSPs, and GPPs in highly integrated assemblies.
Our flagship satellite model, the Boeing 702, is a powerful, scalable product line offering flexible designs that can operate in the geosynchronous, medium-Earth or low-Earth orbital planes. More than 50 have been launched to date. Our newest version is the 702X.
Boeing Commercial Satellites designs and sells communications satellites and payloads for commercial telecommunications, broadband, scientific and environmental applications. Boeing-built spacecraft relay voice and video communications, streaming video content, and direct-to-home entertainment.
Boeing Commercial Satellite Services delivers satellite communications to our partners operating on land, at sea, and in air. Boeing designs secure, scalable, military-grade solutions that are flexible and responsive to dynamic mission needs. Boeing offers a fully managed network service that supports user-operated or automated secure beam commanding, including platform tracking, to enable our customers to steer their capacity anywhere in the world. The benefits we bring to government customers include rapid response to contingency operations, augmented capacity to Wideband Global SATCOM (WGS) satellites and full compatibility with U.S. DoD certified terminals.
Moving at mission-relevant speed to deliver resilient systems to the escalating threat environment, Boeing leverages technological innovation from commercial and government space programs developing best-in-class satellite systems across all orbits and mission sets. With capabilities ranging from payload technology development to designing turnkey end-to-end systems, our products encompass narrowband ultra-high frequency solutions that enable worldwide communication in challenging environments, and protected wideband systems that enable high-capacity broadband connectivity for the U.S. government and its allies.
At first glance, the small white structure perched on a patch of land in Fairbanks, Alaska, looks simple. But for L3Harris, the National Oceanic and Atmospheric Administration (NOAA) and others trying to keep up with a rapid increase in satellite assets, it's game-changing technology.
Our L3Harris team in Fairbanks recently wrapped up a successful three-month demonstration of the DPAAS prototype technology, showcasing its ability to handle an average of more than 300 satellite contacts per day, including up to eight simultaneous contacts.
The project is part of a Cooperative Research and Development Agreement we signed with NOAA in early 2023, as the agency seeks partnerships that will help it gather environmental data from an increasing number of satellites.
Citation: Wang L, Zhang H, Jin L, Wang Q, Shi L, Duan K, Liu P, Han J and Dong H (2023) How to realize digital transformation in satellite communication industry? -- Configuration analysis based on the technology-organization-environment framework. Front. Environ. Sci. 11:1002135. doi: 10.3389/fenvs.2023.1002135
The first company on the list is Viasat, a U.S. communications service provider with nearly 4 decades of experience and a global leader. The Carlsbad, California-headquartered company largely focuses its space communications services on high-speed satellite connectivity and secure network systems for its defense, military, and commercial customers.
Customers of the London-based SatCom leader Inmarsat have access to high throughput and advanced communication services. Two signature offerings, ELERA and Global Xpress (GX), for instance, are used in the following applications and use cases:
Like Eutelsat, Inmarsat has traditionally been a GEO satellite-first company, but has its crosshairs on LEO communication services. The multi-layer network architecture ORCHESTRA, which is for the Asia-Pacific region, will be a hybrid system consisting of 150 to 175 highly targeted LEO satellites alongside a host of GEO satellites and terrestrial 5G communications. ORCHESTRA will target enterprise applications in urban air mobility, Industrial IoT (IIoT), smart cruise ships, and tactical private networks. Eutelsat's hybrid satellite system, due for deployment between 2025 and 2030, will also benefit from mesh networks that will route traffic to and from other terminals.
The increasing number of low earth orbit (LEO) and medium earth orbit (MEO) satellite constellations and a shift toward dedicated ground stations to satellite communications as a service are driving advancements and a change of requirements for both satellite and ground terminal antennas. Ground terminals are now being specified to flexibly track multiple satellites, while satellite antenna systems are being pushed to the limits to realize ambitious high throughput satellite (HTS) goals. A previously theoretical solution to these challenges has been the use of digital beamforming technologies to enable fully steerable, active antennas to enhance capacity, control, and flexibility. The emergence and rapid development of active antenna systems for terrestrial communications has also spurred development of highly integrated and capable digital beamforming (DBF) solutions for satellite applications.
DBF is an alternate strategy to analog beamforming or hybrid beamforming methods of controlling antenna arrays. Analog beamforming (ABF) is the traditional method of beamforming, which uses analog/RF phase shifters and amplitude adjustment, done with either variable attenuators or variable gain amplifiers. Hybrid beamforming uses some digital processing components in the signal chain, often some DSP functions on the baseband processing and frequency translation, which is then sent to analog phase shifters and amplitude adjustment hardware.
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