Doppler Applications in LEO Satellite Communication Systems develops and presents an important class of techniques useful in the construction of little Low Earth Orbit (LEO) satellite communication systems. It centers on the very significant Doppler shift that attends communications through a LEO satellite and shows how this phenomenon can be exploited for an unexpected benefit. The techniques taught in the book are expected to be particularly attractive to system engineers because ground-based transceivers must generally compensate for the large Doppler component and therefore the necessary receiver processing loops are often already in place and expensed. This volume starts with a recounting of the characteristics of a LEO satellite and its orbit. The 2nd chapter addresses the LEO orbital geometry and reviews the Doppler effect attending LEO communications. Chapter three is focused on the important task of estimating the Doppler at a ground terminal. Appropriate signal processing algorithms are reviewed. Chapter four is concerned with predicting LEO satellite visibility. Chapters five and six are, respectively, devoted to the use of the significant LEO Doppler as an aid in a new traffic flow control protocol and as an aid for effecting communications power control. The last chapter describes MATLAB® based analysis. Doppler Applications in LEO Satellite Communication Systems provides a thorough review of the LEO Doppler phenomenon.

Possible doppler shifts due to motions of existing 'stationary' satellites are shown to be as large as 212 Hz/GHz. When the contribution due to ships motion and headway are added, total shifts of 2.5 kHz at X band are possible. To avoid a severe penalty in synchronization acquisition time in operating pseudonoise or frequency hop modems now considered for Naval satellite communication, some type of automatic doppler shift compensation is required. Several compensation methods are described that cannot obtain exact correction without undue complexity but can reduce the compensation error to less than 24 Hz/kHz of beacon carrier doppler shift with relatively simple techniques. Problems of phase noise due to phase lock loop bandwidths required to track changes in doppler shift and local oscillator spectral purity remain as prime problem areas. (Author).

Global Mobile Satellite Systems - A Systems Overview makes mobile satellite communications understandable for communication engineers, candidates for an engineering degree, technicians, managers, and other decision makers such as financiers and regulators. It provides a systems oriented top-level view of mobile satellite communications. In particular, it focuses on Global Mobile Satellite Systems (GMSS) including active programs such as Globalstar, IRIDIUM, ORBCOMM, ACeS, and Thuraya, or so-called the second generation mobile satellite systems class. The authors start with a brief description of three generations of satellite systems in use or planned in the telecommunications industry. Selected systems architectural trades are identified and explained to illustrate how various GMSS systems are formulated, developed and evaluated. It includes an examination of market demand trends, business trades, regulatory issues as well as technical considerations. Major issues are examined in trade study style to provide easy access to key information. Key systems drivers such as orbit trades between LEO's, MEO's, and GEO's, frequency, protocols, customer bases, and regulatory and engineering issues are included. This book should appeal to individuals interested in the basic elements of Global Mobile Satellite Systems.

The updated 6th edition of the authoritative and comprehensive textbook to the field of satellite communications engineering The revised and updated sixth edition of Satellite Communications Systems contains information on the most recent advances related to satellite communications systems, technologies, network architectures and new requirements of services and applications. The authors – noted experts on the topic – cover the state-of-the-art satellite communication systems and technologies and examine the relevant topics concerning communication and network technologies, concepts, techniques and algorithms. New to this edition is information on internetworking with the broadband satellite systems, more intensive coverage of Ka band technologies, GEO high throughput satellite (HTS), LEO constellations and the potential to support the current new broadband Internet services as well as future developments for global information infrastructure. The authors offer details on digital communication systems and broadband networks in order to provide high-level researchers and professional engineers an authoritative reference. In addition, the book is designed in a user-friendly format. This important text: Puts the focus on satellite communications and networks as well as the related applications and services Provides an essential, comprehensive and authoritative updated guide to the topic Contains new topics including the space segment, ground, ground satellite control and network management, relevant terrestrial networks and more Includes helpful illustrations, tables and problems to enhance learning Offers a summary at the beginning of each chapter to help understand the concepts and principles discussed Written for research students studying or researching in the areas related to satellite communications systems and networks, the updated sixth edition of Satellite Communications Systems offers an essential guide to the most recent developments in the field of satellite communications engineering and references to international standards.