Noise Temperature Theory and Applications for Deep Space Communications Antenna Systems /by Tom Y. Otoshi (Author).Confidently predict receiver system noise temperature using the techniques developed for NASA-JPL's Deep Space Network techniques presented, for the first time, in this groundbreaking resource. The book shows you how to analyze, design, measure and accurately evaluate the many detailed elements comprising noise temperature.After a thorough introductory overview, you delve into reflector performance issues, including material conductivity, perforations, protective coatings, the effects of terrestrial weather, and the influence of the Earth's Sun. This in-depth reference covers mismatch error equations, in terms of both reflection coefficient magnitudes and VSWRs. Moreover, you find expert guidance in calibrating system noise temperature and antenna efficiency. The book includes easy-to-use formulas that enable you to calculate noise temperature of solid metallic reflector surfaces and of leaks in perforated plates or wire grids. What's more, you get an invaluable tutorial on using S- parameters to predict noise temperature of multiports.

Mobile Lightweight Wireless Systems: First International ICST Conference, MOBILIGHT 2009, Athens, Greece, May 18-20, 2009, Revised Selected Papers /by Fabrizio Granelli (Editor), Charalabos Skianis (Editor), Periklis Chatzimisios (Editor), Yang Xiao (Editor), Simone Redana (Editor).This book constitutes the proceedings of the First International ICST Conference, MOBILIGHT 2009 held in Athens, Greece in May 2009.

The 40 full papers presented focus on topics such as WPAN, WLAN, WMAN/cellular as well as architectures and design methodologies to support seamless access to the comunication facility. Further contents are services, in the vison of "always on" requirements as well as business models, oportunities and solutions.
This volume reflects the current request for lighweight, wireless communication devices with high usability and performance able to support added-value service in a highly mobile environment.

 

Author(s) : Xuemin Shen, Mohsen Guizani, Robert Caiming Qiu, Tho Le-Ngoc
Publisher : Wiley
Year : Feb 2006
ISBN 10 : 0470011440
ISBN 13 : 9780470011447
Language : English
Pages : 322
File type : PDF
Size : 2.8 MB

A UWB system is defined as any radio system that has a 10-dB bandwidth larger than 20 % of its center frequency, or has a 10-dB bandwidth equal to or larger than 500 MHz. The recent approval of UWB technology by Federal Communications Commission (FCC) of the United States reserves the unlicensed frequency band between 3.1 and 10.6 GHz (7.5 GHz) for indoor UWB wireless communication systems. It is expected that many conventional principles and approaches used for short-range wireless communications will be reevaluated and a new industrial sector in short-range (e.g., 10 m) wireless communications with high data rate (e.g., 400 Mbps) will be formed. Further, industrial standards IEEE 802.15.3a (high data rate) and IEEE 802.15.4a (very low data rate) based on UWB technology have been introduced.

UWB technology has many benefits owing to its ultra-wideband nature, which include high data rate, less path loss and better immunity to multipath propagation, availability of low-cost transceivers, low transmit power and low interference, and so on. On the other hand, there exist many technical challenges in UWB deployment, such as the received-waveform distortion from each distinct delayed propagation path, antenna design for and synchronization of very short pulses, performance degradation due to multiple access interference and narrowband jamming, employment of higher order modulation schemes to improve capacity or throughput, and development of link and network layers to take advantage of the UWB transmission benefits at the physical layer.

Even though R&D results so far have demonstrated that UWB radio is a promising solution for high-rate short-range wireless communications, further extensive investigation, experiments, and development are necessary for developing effective and efficient UWB communication systems and UWB technology. This book is timely in reporting the results from cutting edge research and state-of-the-art technology in UWB wireless communications.

Author(s) : Jim Geier
Publisher : Cisco Press
Year : Aug 2004
ISBN 10: 1587201119
ISBN 13: 9781587201110
Language : English
Pages : 264
File type : CHM
Size : 1.2 MB

As a basic introduction to wireless networking, Wireless Networks First-Step assumes that readers have no previous wireless experience. The book provides an overview of wireless networking, along with details of applicable standards and technologies. Newcomers to wireless technologies will find practical information along with an abundance of examples. Case studies throughout the chapters provide real-world implementation examples, presented in a non-technical fashion. Implementation details are discussed only to the extent that readers can identify what type of wireless network may be appropriate for their needs.

The intent of this book is to offer a basic introduction to wireless network applications, components, and technologies. These concepts provide a solid basis for understanding various wireless network topics in more detail. After reading this book, you'll be able to effectively continue a study of specific wireless networks.

This book was written for anyone beginning a study of wireless networks. There is no need for readers to have a technical background. CEOs, managers, and business owners will benefit from reading this book, as will engineers and technicians. Even users wanting to understand the inner workings of wireless networks will find this book interesting.

Author(s) : Kaveh Pahlavan, Allen H. Levesque
Publisher : Wiley
Year : Oct 2005
ISBN 10 : 0471725420
ISBN 13 : 9780471725428
Language : English
Pages : 738
File type : PDF
Size : 8.3 MB

That book presented wireless networking as the enabling communications technology of the 1990s and beyond. Now, only a decade later, mobile and portable telephones and wireless data services are a familiar part of our daily lives, as the twenty-first century witnesses widespread deployment of wireless networks, which has revolutionized the concept of communication and information processing for business, professional, and private applications. The field of wireless communications continues to experience unprecedented market growth, as evidenced by over 1.5 billion cellular telephone subscribers worldwide and the rapid increase in the size of the wireless local area network market for office, home, and public access applications.

The book is written from a systems engineering perspective, by which we mean that the various technical topics are presented in the context of ongoing development of specific new systems and services, as well as key recent developments in national and international spectrum allocations and standards.

Our method of presentation is to organize the myriad of emerging wireless technologies into logical categories that reflect the variety of perspectives that users have toward different networks and services. The book addresses the major segments of wireless technology: first-, second-, and third-generation wide-area cellular networks, wireless local area networks (WLANs), and wireless personal area networks (WPANs), with special attention to the emerging location-aware broadband wireless sensor and ad hoc networks. Although the book covers technology applicable to a wide range of wireless systems, as in the first edition, particular attention is given to indoor wireless communications, an area that is not treated in great depth in most other books.