To meet the future demand for huge traffic volume of wireless data service, the research on the fifth generation (5G) mobile communication systems has been undertaken in recent years. It is expected that the spectral and energy efficiencies in 5G mobile communication systems should be ten-fold higher than the ones in the fourth generation (4G) mobile communication systems. Therefore, it is IMPortant to further exploit the potential of spatial multiplexing of multiple antennas. In the last twenty years, multiple-input multiple-output (MIMO) antenna techniques have been considered as the key techniques to increase the capacity of wireless communication systems. When a large-scale antenna array (which is also called massive MIMO) is equipped in a base-station, or a large number of distributed antennas (which is also called large-scale distributed MIMO) are deployed, the spectral and energy efficiencies can be further improved by using spatial domain multiple access. This paper provides an overview of massive MIMO and large-scale distributed MIMO systems, including spectral efficiency analysis, channel state information (CSI) acquisition, wireless transmission technology, and resource allocation.
標(biāo)簽： Large-scale Antenna Systems
上傳時(shí)間： 2020-05-27
上傳用戶：shancjb
Mobile radio networks have risen in prominence over the last few years, primarily by the rise in popularity of cellular phones. It is IMPortant to recognise however that mobile radio technology fulfils a far wider range of applications that meet the demands of the modern world. These include the networks that allow police and emergency services to serve the public, military networks for operations and humanitarian support, and the mobile technol- ogies that are vital to the safety of aircraft.
標(biāo)簽： Network Mobile Design Radio
上傳時(shí)間： 2020-05-30
上傳用戶：shancjb
At the macroscopic level of system layout, the most IMPortant issue is path loss. In the older mobile radio systems that are limited by receiver noise, path loss determines SNR and the maximum coverage area. In cellular systems, where the limiting factor is cochannel interference, path loss determines the degree to which transmitters in different cells interfere with each other, and therefore the minimum separation before channels can be reused.
標(biāo)簽： Characteristics Channel Mobile
上傳時(shí)間： 2020-05-30
上傳用戶：shancjb
The insinuation of telecommunications into the daily fabric of our lives has been arguably the most IMPortant and surprising development of the last 25 years. Before this revolution, telephone service and its place in our lives had been largely stable for more than a generation. The growth was, so to speak, lateral, as the global reach of telecommunications extended and more people got telephone service. The distinction between oversea and domestic calls blurred with the advances in switching and transmission, undersea cable, and communication satellites. Traffic on the network remained overwhelmingly voice, largely in analog format with facsimile (Fax) beginning to make inroads.
標(biāo)簽： Telecommunications Modeling Analysis and of
上傳時(shí)間： 2020-05-31
上傳用戶：shancjb
Multi-carrier modulation? Orthogonal Frequency Division Multi- plexing (OFDM) particularly? has been successfully applied to a wide variety of digital communications applications over the past several years. Although OFDM has been chosen as the physical layer standard for a diversity of IMPortant systems? the theory? algorithms? and implementation techniques remain subjects of current interest. This is clear from the high volume of papers appearing in technical journals and conferences.
標(biāo)簽： COMMUNICATIONS MULTI-CARRIER DIGITAL
上傳時(shí)間： 2020-05-31
上傳用戶：shancjb
Advances in communication and networking technologies are rapidly making ubiq- uitous network connectivity a reality. Wireless networks are indispensable for supporting such access anywhere and at any time. Among various types of wire- less networks, multihop wireless networks (MWNs) have been attracting increasing attention for decades due to its broad civilian and military applications. Basically, a MWN is a network of nodes connected by wireless communication links. Due to the limited transmission range of the radio, many pairs of nodes in MWNs may not be able to communicate directly, hence they need other intermediate nodes to forward packets for them. Routing in such networks is an IMPortant issue and it poses great challenges.
標(biāo)簽： Multihop Wireless Networks
上傳時(shí)間： 2020-05-31
上傳用戶：shancjb
Never have telecommunications operations and network management been so IMPortant. Never has it been more IMPortant to move away from practices that date back to the very beginning of the telecommunications industry. Building and con- necting systems internally at low cost, on an as - needed basis, and adding software for supporting new networks and services without an overall architectural design will not be cost effective for the future. Defi ning operations and network manage- ment requirements at the 11th hour for new technologies, networks, and services deployments must also change.
標(biāo)簽： Telecommunications Generation Networks Next
上傳時(shí)間： 2020-05-31
上傳用戶：shancjb
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.
標(biāo)簽： Communications Physical Security Wireless Layer in
上傳時(shí)間： 2020-05-31
上傳用戶：shancjb
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.
標(biāo)簽： communication Principles digital of
上傳時(shí)間： 2020-05-31
上傳用戶：shancjb
This book on Project Management is intended as a quick reference covering IMPortant aspects of project management that should be understood by managers in the telecommunications environment. This book is organized with an introduction, which introduces the value chain in telecommunications and illustrates the type of project, which one might encounter in a telecommunications company.
標(biāo)簽： Telecommunications Management Managers Project
上傳時(shí)間： 2020-05-31
上傳用戶：shancjb
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