Over the past ten years there has been a revolution in the devel- opment and acceptance of mobile products. In that period, cel- lular telephony and consumer electronics have moved from the realm of science fiction to everyday reality. Much of that revolu- tion is unremarkable – we use wireless, in its broadest sense, for TV remote controls, car keyfobs, travel tickets and credit card transactions every day. At the same time, we have increased the number of mobile devices that we carry around with us. However, in many cases the design and function of these and other static products are still constrained by the wired connections that they use to transfer and share data.
标签: Short-Range Essentials Wireless of
上传时间: 2020-05-27
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Currently, the information and communications technology (ICT) industry sector accounts for about 2–6% of the energy consumption worldwide, and a significant por- tion of this is contributed by the wireless and mobile communications industry. With the proliferation of wireless data applications, wireless technology continues to increase worldwide at an unprecedented growth rate. This has resulted in an increased number of installed base stations and higher demand on power grids and device power usage, causing an increased carbon footprint worldwide.
标签: Communication Networks Green Radio
上传时间: 2020-05-27
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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.
标签: Heterogeneous Wireless Networks Access
上传时间: 2020-05-27
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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.
标签: High-Frequency Oscillator Design
上传时间: 2020-05-27
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Nature is seldom kind. One of the most appealing uses for radio- telephone systems—communication with people on the move—must over- come radio transmission problems so difficult they challenge the imagina- tion. A microwave radio signal transmitted between a fixed base station and a moving vehicle in a typical urban environment exhibits extreme variations in both amplitude and apparent frequency.
标签: Communications Microwave Mobile
上传时间: 2020-05-28
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This book is exclusively dedicated to WiMAX. The focus of the book is on the applications of WiMAX networks, with delivery of multimedia content to wireless and mobile devices being the area of greatest atten- tion. WiMAX has crossed a number of major milestones in the recent past.
标签: Mobile Broadcasting with WiMAX Principles
上传时间: 2020-05-30
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By definition, the term “mobile-radio communications” describes any radio communication link between two terminals of which one or both are in motion or halted at unspecified locations and of which one may actually be a fixed terminal such as a base station. This definition applies to both mobile-to-mobile and mobile-to-fixed radio communica- tion links. The mobile-to-mobile link could in fact consist of a mobile- to-fixed-to-mobile radio communication link.The term “mobile” applies to land vehicles, ships at sea, aircraft, and communications satellites. In tactical situations, mobile-radio systems may include any or all of these types of mobile terminals.
标签: Communications Engineering Mobile
上传时间: 2020-05-30
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Mobile wireless communications are in constant evolution due to the continu- ously increasing requirements and expectations of both users and operators. Mass multimedia* services have been for a long time expected to generate a large amount of data traffic in future wireless networks [1]. Mass multimedia services are, by definition, purposed for many people. In general, it can be distinguished between the distribution of any popular content over a wide area and the distribu- tion of location-dependent information in highly populated areas. Representative examples include the delivery of live video streaming content (like sports compe- titions, concerts, or news) and file download (multimedia clips, digital newspa- pers, or software updates).
标签: Broadcasting Generation Mobile Next
上传时间: 2020-05-31
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The goal of this book is to provide a concise but lucid explanation and deriva- tion of the fundamentals of spread-spectrum communication systems. Although spread-spectrum communication is a staple topic in textbooks on digital com- munication, its treatment is usually cursory, and the subject warrants a more intensive exposition. Originally adopted in military networks as a means of ensuring secure communication when confronted with the threats of jamming and interception, spread-spectrum systems are now the core of commercial ap- plications such as mobile cellular and satellite communication.
标签: Principles Spectrum Spread of
上传时间: 2020-05-31
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Communication protocols – for short protocols – form the basis for the opera- tion of computer networks and telecommunication systems. They are behavior conventions which describe how communication systems interact with each other in computer networks. Protocols define the temporal order of the interactions and the formats of the data units exchanged. Communication protocols comprise a wide range of different functions and mechanisms, such as the sending and receiv- ing of data units, their coding/decoding, error control mechanisms, timer control, flow control, and many others.
标签: Engineering Protocol
上传时间: 2020-05-31
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