This book is a result of the recent rapid advances in two related technologies: com- munications and computers. Over the past few decades, communication systems have increased in complexity to the point where system design and performance analysis can no longer be conducted without a significant level of computer sup- port. Many of the communication systems of fifty years ago were either power or noise limited. A significant degrading effect in many of these systems was thermal noise, which was modeled using the additive Gaussian noise channel.
標簽: Communication Principles Simulation Systems of
上傳時間: 2020-05-31
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It was only a few years ago that “ubiquitous connectivity” was recognized as the future of wireless communication systems. In the era of ubiquitous connectivity, it was expected that the broadband mobile Internet experience would be pervasive, and seamless connectivity on a global scale would be no surprise at all. The quality of service would be guaranteed no matter when/where/what the users wanted with the connectivity. Connectivity would even be extended to object-to-object communication, where no human intervention was required. All objects would become capable of autonomous communication.
標簽: Protocols Radio LTE-A LTE for and
上傳時間: 2020-06-01
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Digital mobile wireless communication and the Internet have undergone a fantastic growth in the last few years and, despite originating from two different worlds, they are converging. This convergence corresponds to the evolution of mobile systems towards the highest broadband data transmissions (GSM, EDGE/GPRS, UMTS then HSDPA), while the computing world gets equipped with wireless technologies such as Wi-Fi or Wi-Max.
標簽: Reconfigurable Systems Mobile Radio
上傳時間: 2020-06-01
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Developers, manufacturers and marketers of products incorporating short- range radio systems are experts in their fields—security, telemetry, medical care, to name a few. Often they add a wireless interface just to eliminate wires on an existing wired product. They may adapt a wireless subsystem, which is easy to integrate electrically into their system, only to find that the range is far short of what they expected, there are frequent false alarms, or it doesn’t work at all. It is for these adapters of wireless subsystems that this book is primarily intended.
標簽: Communication Short-range Wireless
上傳時間: 2020-06-01
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The serious study of the practice of how to determine the appropriate content of a specification is a seldom-appreciated pastime. Those who have the responsibility to design a product would prefer a greater degree of freedom than permitted by the con- tent of a specification. Many of those who would manage those who would design a product would prefer to allocate all of the project funding and schedule to what they consider more productive labor. These are the attitudes, of course, that doom a project to defeat but they are hard to counter no matter how many times repeated by design engineers and managers. A system engineer who has survived a few of these experiences over a long career may retire and forget the past but we have an endur- ing obligation to work toward changing these attitudes while trying to offer younger system engineers a pathway toward a more sure success in requirements analysis and specification publishing.
標簽: Requirements Analysis System
上傳時間: 2020-06-01
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When 3GPP started standardizing the IMS a few years ago, most analysts expected the number of IMS deploymentsto grow dramatically as soon the initial IMS specifications were ready (3GPP Release 5 was functionallyfrozenin the first half of 2002and completedshortly after that). While those predictions have proven to be too aggressive owing to a number of upheavals hitting the ICT (Information and Communications Technologies) sector, we are now seeing more and more commercial IMS-based service offerings in the market. At the time of writing (May 2008), there are over 30 commercial IMS networks running live traffic, addingup to over10million IMS users aroundthe world; the IMS is beingdeployedglobally. In addition, there are plenty of ongoing market activities; it is estimated that over 130 IMS contracts have been awarded to all IMS manufacturers. The number of IMS users will grow substantially as these awarded contracts are launched commercially. At the same time, the number of IMS users in presently deployed networks is steadily increasing as new services are introduced and operators running these networks migrate their non-IMS users to their IMS networks.
標簽: Multimedia Subsystem The IMS 3G IP
上傳時間: 2020-06-01
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Digital radios have undergone an astonishing evolution in the last century. Born as a set of simple and power-hungry electrical and electromechanical devices for low data rate transmission of telegraph data in the Marconi age, they have transformed, thanks to substantial advances in electronic technology, into a set of small, reliable and sophisticated integrated devices supporting broadband multimedia communications. This, however, would not have been possible unless significant progress had been made in recent decades in the field of signal processing algorithms for baseband and passband signals. In fact, the core of any modern digital radio consists of a set of algorithms running over programmable electronic hardware. This book stems from the research and teaching activities of its co-authors in the field of algorithmic techniques for wireless communications. A huge body of technical literature has accumulated in the last four decades in this area, and an extensive coverage of all its important aspects in a single textbook is impossible. For this reason, we have selected a few important topics and, for ease of reading, organized them into two parts.
標簽: Communications Algorithmic Techniques Wireless
上傳時間: 2020-06-01
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The goal of this book is to introduce the simulation methods necessary to describe the behaviour of semiconductor devices during an electrostatic discharge (ESD). The challenge of this task is the correct description of semiconductor devices under very high current density and high temperature transients. As it stands, the book can be no more than a snapshot and a summary of the research in this field during the past few years. The authors hope that the book will provide the basis for further development of simulation methods at this current frontier of device physics.
標簽: Development Protection ESD
上傳時間: 2020-06-05
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Since electronic equipment was first developed, static electricity has been a source of problems for users and designers. In the last few years, however, electrostatic discharge (ESD) has become a source of major problems. This has occurred because newer electronic devices, such as integrated circuits, are much more susceptible to ESD problems than previous devices, such as vacuum tubes. Another trend compounding this ESD susceptibility problem is the spread of sophisticated equipment into home and office environments where ESD is quite common.
標簽: Electronic Equipment ESD and
上傳時間: 2020-06-05
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For more than three decades, Micro Electro Mechanical Systems (MEMS) have steadily transitioned out of research labs and into production forming a more than $10 billion market [1]. MEMS devices such as accelerometers, pressure sensors and microphones, to name a few, have seen immense utilization, particularly in the consumer electronics market, because of their compact sizes and minute power consumptions. In addition, these devices benefit from batch fabrication, which has enabled year-over-year reductions in cost [2]. In recent years,
上傳時間: 2020-06-06
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