Ever since ancient times, people continuously Have devised new techniques and technologies for communicating their ideas, needs, and desires to others. Thus, many forms of increasingly complex communication systems Have appeared over the years. The basic motivations behind each new one were to improve the transmission fidelity so that fewer errors occur in the received message, to increase the transmission capacity of a communication link so that more infor- mation could be sent, or to increase the transmission distance between relay sta- tions so that messages can be sent farther without the need to restore the signal fidelity periodically along its path.
标签： Communications Essentials Optical
上传时间： 2020-05-31
上传用户：shancjb
Recent decades Have shown a tremendous expansion of the Internet. The number of connected terminals has increased by orders of magnitude, traffic has grown exponen- tially, coverage has become ubiquitous and worldwide, and today’s sophisticated Web 2.0 applications are increasingly providing services which hitherto Have been the realm of telecommunications, such as Skype and video conferencing. This has even led to the thought that access to the Internet might one day be a universal right of every citizen. This evolution will accelerate in the coming decades.
标签： Networking Personal Networks Wireless
上传时间： 2020-05-31
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The ever-increasing demand for private and sensitive data transmission over wireless net- works has made security a crucial concern in the current and future large-scale, dynamic, and heterogeneous wireless communication systems. To address this challenge, computer scientists and engineers Have tried hard to continuously come up with improved crypto- graphic algorithms. But typically we do not need to wait too long to find an efficient way to crack these algorithms. With the rapid progress of computational devices, the current cryptographic methods are already becoming more unreliable. In recent years, wireless re- searchers Have sought a new security paradigm termed physical layer security. Unlike the traditional cryptographic approach which ignores the effect of the wireless medium, physi- cal layer security exploits the important characteristics of wireless channel, such as fading, interference, and noise, for improving the communication security against eavesdropping attacks. This new security paradigm is expected to complement and significantly increase the overall communication security of future wireless networks.
标签： Communications Physical Security Wireless Layer in
上传时间： 2020-05-31
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Transmit power in wireless cellular networks is a key degree of freedom in the management of interference, energy, and connectivity. Power control in both uplink and downlink of a cellular network has been extensively studied, especially over the last 15 years, and some of the results Have enabled the continuous evolution and significant impact of the digital cellular technology.
标签： Cellular Networks Wireless Control Power in
上传时间： 2020-05-31
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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.
标签： Communication Principles Simulation Systems of
上传时间： 2020-05-31
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Communication has been one of the deepest needs of the human race throughout recorded history. It is essential to forming social unions, to educating the young, and to expressing a myriad of emotions and needs. Good communication is central to a civilized society. The various communication disciplines in engineering Have the purpose of providing technological aids to human communication. One could view the smoke signals and drum rolls of primitive societies as being technological aids to communication, but communication technology as we view it today became important with telegraphy, then telephony, then video, then computer communication, and today the amazing mixture of all of these in inexpensive, small portable devices.
标签： communication Principles digital of
上传时间： 2020-05-31
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Mobile operators must continuously pursue cost‐ effective and efficient solutions to meet the high data demand requirements of their subscribers. Limited spectrum allocations and non‐contiguous spectrum blocks continue to pose challenges for mobile operators supporting large data uploads and downloads across their networks. With the increase in video and social media content, the challenges Have increased exponentially.
标签： qorvo-carrier-aggregation-fundame ntals
上传时间： 2020-05-31
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Quality of Service ( QoS ) has always been in a world of its own, but as the technology has been refi ned and has evolved in recent years, QOS usage has increased to the point where it is now considered a necessary part of network design and operation. As with most technologies, large - scale deployments Have led to the technology becoming more mature, and QOS is no exception.
标签： QOS-Enabled Networks
上传时间： 2020-05-31
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This book provides the essential design techniques for radio systems that operate at frequencies of 3 MHz to 100 GHz and which will be employed in the telecommunication service. We may also call these wireless systems, wireless being synonymous with radio, Telecommunications is a vibrant indus- try, particularly on the ‘‘radio side of the house.’’ The major supporter of this upsurge in radio has been the IEEE and its 802 committees. We now devote Ž . an entire chapter to wireless LANs WLANs detailed in IEEE 802.11. We also now Have subsections on IEEE 802.15, 802.16, 802.20 and the wireless Ž . Ž metropolitan area network WMAN . WiFi, WiMax,, and UWB ultra wide- . band are described where these comparatively new radio specialties are demonstrating spectacular growth.
标签： Telecommunication Design System Radio for
上传时间： 2020-06-01
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We are currently witnessing an increase in telecommunications norms and standards given the recent advances in this domain. The increasing number of normalized standards paves the way for an increase in the range of offers and services available for each consumer. Moreover, the majority of available radio frequencies Have already been allocated.
标签： Allocation Resource Radio
上传时间： 2020-06-01
上传用户：shancjb
