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.
标签： Communication Strategies Feedback Wireless for
上传时间： 2020-05-27
上传用户：shancjb
Free Space Optical Communication (FSOC) is an effective alternative technology to meet the Next Generation Network (NGN) demands as well as highly secured (mili- tary) communications. FSOC includes various advantages like last mile access, easy installation, free of Electro Magnetic Interference (EMI)/Electro Magnetic Compatibil- ity (EMC) and license free access etc. In FSOC, the optical beam propagation in the turbulentatmosphereisseverelyaffectedbyvariousfactorssuspendedintheCHANNEL, geographicallocationoftheinstallationsite,terraintypeandmeteorologicalchanges. Therefore a rigorous experimental study over a longer period becomes significant to analyze the quality and reliability of the FSOC CHANNEL and the maximum data rate that the system can operate since data transmission is completely season dependent.
标签： Communication Optical System Space Free
上传时间： 2020-05-27
上传用户：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.
标签： High-Frequency Oscillator Design
上传时间： 2020-05-27
上传用户：shancjb
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.
标签： Large-scale Antenna Systems
上传时间： 2020-05-27
上传用户：shancjb
In the nineteenth century, scientists, mathematician, engineers and innovators started investigating electromagnetism. The theory that underpins wireless communications was formed by Maxwell. Early demonstrations took place by Hertz, Tesla and others. Marconi demonstrated the first wireless transmission. Since then, the range of applications has expanded at an immense rate, together with the underpinning technology. The rate of development has been incredible and today the level of technical and commercial maturity is very high. This success would not have been possible without understanding radio- wave propagation. This knowledge enables us to design successful systems and networks, together with waveforms, antennal and transceiver architectures. The radio CHANNEL is the cornerstone to the operation of any wireless system.
标签： LTE-Advanced Generation Next and
上传时间： 2020-05-27
上传用户：shancjb
LTE-Advanced becomes a truly global standard for 4G cellular communications. Relay, as one of the key technologies of LTE-Advanced, can significantly extend the coverage, and improve the system throughput. LTE-A standards and tech- nologies were described in several recent books where the limited pages for relay feature prevent the detailed explanations of the technology. In this book, we tried to provide an in-depth description of LTE-A relay development. More specifically, significant portions are spent on relay CHANNEL modeling and potential technologies during the study item phase of the development, although some of those tech- nologies, such as Type 2 cooperative relay, multi-hop relay, relay with backhaul of carrier aggregation, were not standardized in Release 10 LTE.
标签： LTE-Advanced Technology Relay
上传时间： 2020-05-27
上传用户：shancjb
MIMO-OFDM is a key technology for next-generation cellular communications (3GPP-LTE, Mobile WiMAX, IMT-Advanced) as well as wireless LAN (IEEE 802.11a, IEEE 802.11n), wireless PAN (MB-OFDM), and broadcasting (DAB, DVB, DMB). This book provides a comprehensive introduction to the basic theory and practice of wireless CHANNEL modeling, OFDM, and MIMO, with MATLAB ? programs to simulate the underlying techniques on MIMO-OFDMsystems.Thisbookisprimarilydesignedforengineersandresearcherswhoare interested in learning various MIMO-OFDM techniques and applying them to wireless communications.
标签： Communications MIMO-OFDM Wireless MATLAB with
上传时间： 2020-05-28
上传用户：shancjb
With this book at your fingertips, you, the reader, and I have something in common. We share the same interest in mobile radio CHANNELs. This area attracted my interest first in autumn 1992 whenImovedfromindustrytoacademiatofindachallengeinmylifeandtopursueascientific career. Since then, I consider myself as a student of the mobile radio CHANNEL who lives for modelling, analyzing, and simulating them. While the first edition of this book resulted from my teaching and research activities at the Technical University of Hamburg-Harburg (TUHH), Germany, the present second edition is entirely an outcome of my work at the University of Agder, Norway.
上传时间： 2020-05-30
上传用户：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.
标签： Characteristics CHANNEL Mobile
上传时间： 2020-05-30
上传用户：shancjb
The family of recent wireless standards included the optional employment of Multiple-Input Multiple-Output(MIMO)techniques.This was motivatedby the observationaccordingto the classic Shannon–Hartley law that the achievable CHANNEL capacity increases logarithmically with the transmit power. In contrast, the MIMO capacity increases linearly with the number of transmit antennas, provided that the number of receive antennas is equal to the number of transmit antennas. With the further proviso that the total transmit power is increased in proportion to the number of transmit antennas, a linear capacity increase is achieved upon increasing the transmit power, which justifies the spectacular success of MIMO systems.
标签： Multi-Functional Systems MIMO
上传时间： 2020-05-31
上传用户：shancjb
