In recent years, cellular voice networks have transformed into powerful packet-switched access networks for both voice communication and Internet access. Evolving Universal Mobile Telecommunication System (UMTS) networks and first Long Term Evolution (LTE) installations now deliver bandwidths of several megabits per second to individual users, and mobile access to the Internet from handheld devices and notebooks is no longer perceived as slower than a Digital Subscriber Line (DSL) or cable connection. Bandwidth and capacity demands, however, keep rising because of the increasing number of people using the networks and because of bandwidth-intensive applications such as video streaming. Thus, network manufacturers and network operators need to find ways to continuously increase the capacity and performance of their cellular networks while reducing the cost.
標簽： BRINGING NETWORKS Beyond and 3G 4G
上傳時間： 2020-05-26
上傳用戶：shancjb
The Internet of Things is considered to be the next big opportunity, and challenge, for the Internet engineering community, users of technology, companies and society as a whole. It involves connecting embedded devices such as sensors, home appliances, weather stations and even toys to Internet Protocol (IP) based networks. The number of IP-enabled embedded devices is increasing rapidly, and although hard to estimate, will surely outnumber the number of personal computers (PCs) and servers in the future. With the advances made over the past decade in microcontroller,low-power radio, battery and microelectronic technology, the trend in the industry is for smart embedded devices (called smart objects) to become IP-enabled, and an integral part of the latest services on the Internet. These services are no longer cyber, just including data created by humans, but are to become very connected to the physical world around us by including sensor data, the monitoring and control of machines, and other kinds of physical context. We call this latest frontier of the Internet, consisting of wireless low-power embedded devices, the Wireless Embedded Internet. Applications that this new frontier of the Internet enable are critical to the sustainability, efficiency and safety of society and include home and building automation, healthcare, energy efficiency, smart grids and environmental monitoring to name just a few.
標簽： Embedded Internet Wireless 6LoWPAN The
上傳時間： 2020-05-26
上傳用戶：shancjb
Firstly, this book is set at a level suitable for senior undergraduate and postgraduate students who wish to understand the fundamentals and applications of adaptive array antenna systems. Array fundamentals are described in the text, and examples which demonstrate theoretical concepts are included throughout the book, as well as summaries and questions at the end of each chapter.
標簽： Applications Fundamentals Adaptive Systems Array and
上傳時間： 2020-05-26
上傳用戶：shancjb
The very title of this book is borrowed from the information theory vocabulary, and, quite naturally, it is an outline of this theory that will serve as an introduction. The subject of information theory is the scientific study of communications. To this end it defines a quantitative measurement of the communicated content, i.e. informa- tion, and deals with two operations essential for communication techniques: source coding and channel encoding.
標簽： Communication Networks Channel Coding in
上傳時間： 2020-05-26
上傳用戶：shancjb
Many times I have been asked to explain “ briefl y ” how SDH, SONET, and the OTN “ exactly ” work. The questions came mainly from new colleagues, stu- dents, and users of these technologies, personally or via the usenet newsgroup comp.dcom.sdh - sonet. I could have referred them to the standards documents, but to provide a more consistent and clear answer I decided to write this pocket guide. The objective of this book is that it can be used both as an introduction as well as a reference guide to these technologies and their spe- cifi c standards documents.
標簽： Generation Transport Optical ComSoc Guide
上傳時間： 2020-05-27
上傳用戶：shancjb
The General Packet Radio Service (GPRS) allows an end user to send and receive data in packet transfer mode within a public land mobile network (PLMN) without using a permanent connection between the mobile station (MS) and the external network during data transfer. This way, GPRS opti- mizes the use of network and radio resources (RRs) since, unlike circuit- switched mode, no connection between the MS and the external network is established when there is no data flow in progress. Thus, this RR optimiza- tion makes it possible for the operator to offer more attractive fees.
上傳時間： 2020-05-27
上傳用戶：shancjb
During the past decade, many wireless communication techniques have been developedto achievevariousgoals suchas higherdata rate,morerobustlink quality, and higher number of users in a given bandwidth. For wireless communication systems, depending on the availability of a feedback link, two approaches can be considered: namely open and closed loop. Open loop communication system that does not exploit the channel knowledge at the transmitter is now well understood from both a theoretical and practical point of view.
標簽： Communication Strategies Feedback Wireless for
上傳時間： 2020-05-27
上傳用戶：shancjb
This book is an entry-level text on the technology of telecommunications. It has been crafted with the newcomer in mind. The eighteen chapters of text have been prepared for high-school graduates who understand algebra, logarithms, and basic electrical prin- ciples such as Ohm’s law. However, many users require support in these areas so Appen- dices A and B review the essentials of electricity and mathematics through logarithms.
標簽： Telecommunications Fundamentals 1st of ed
上傳時間： 2020-05-27
上傳用戶：shancjb
With the rapid growth in the number of wireless applications, services and devices, using a single wireless technology such as a second generation (2G) and third gener- ation (3G) wireless system would not be efficient to deliver high speed data rate and quality-of-service (QoS) support to mobile users in a seamless way. The next genera- tion wireless systems (also sometimes referred to as Fourth generation (4G) systems) are being devised with the vision of heterogeneity in which a mobile user/device will be able to connect to multiple wireless networks (e.g., WLAN, cellular, WMAN) simultaneously.
標簽： Heterogeneous Wireless Networks Access
上傳時間： 2020-05-27
上傳用戶：shancjb
OSCILLATORS are key building blocks in integrated transceivers. In wired and wireless communication terminals, the receiver front-end selects, amplifies and converts the desired high-frequency signal to baseband. At baseband the signal can then be converted into the digital domain for further data processing and demodula- tion. The transmitter front-end converts an analog baseband signal to a suitable high- frequency signal that can be transmitted over the wired or wireless channel.
標簽： High-Frequency Oscillator Design
上傳時間： 2020-05-27
上傳用戶：shancjb
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