Regardless of the branch of science or engineering, theoreticians have always been enamored with the notion of expressing their results in the form of closed-form expressions. Quite often, the elegance of the closed-form solution is overshadowed by the complexity of its form and the difficulty in evaluating it numerically. In such instances, one becomes motivated to search instead for a solution that is simple in form and simple to evaluate.
标签: Communication CHANNELs Digital Fading over 1st
上传时间: 2020-05-27
上传用户:shancjb
Regardless of the branch of science or engineering, theoreticians have always been enamored with the notion of expressing their results in the form of closed-form expressions. Quite often the elegance of the closed-form solution is overshadowed by the complexity of its form and the difficulty in evaluating it numerically. In such instances, one becomes motivated to search instead for a solution that is simple in form and likewise simple to evaluate.
标签: Communication CHANNELs Digital Fading over 2nd
上传时间: 2020-05-27
上传用户:shancjb
Multiuser multiple-input-multiple-output (MU- MIMO) systems are known to be hindered by dimensionality loss due to channel state information (CSI) acquisition overhead. In this paper, we investigate user-scheduling in MU-MIMO systems on account of CSI acquisition overhead, where a base station dynamically acquires user CHANNELs to avoid choking the system with CSI overhead.
标签: Acquisition Dynamic Channel
上传时间: 2020-05-27
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Communication today is not as easy as it was in the past. Protecting numerous com- munication services, which are operating in the same or adjacent communication CHANNELs, has become increasingly challenging. Communication systems have to be protected from both natural and manmade interference. Electromagnetic interfer- ence can be radiated or conducted, intentional or unintentional.
标签: Communication Protection Systems EMI for
上传时间: 2020-05-27
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The writing of this book was prompted by two main developments in wireless communications in the past decade. First is the huge surge of research activities in physical-layer wireless communication theory. While this has been a subject of study since the 60’s, recent developments in the field, such as opportunistic and multi-input multi-output (MIMO) communication techniques, have brought completely new per- spectives on how to communicate over wireless CHANNELs.
标签: Communication Fundamentals Wireless of
上传时间: 2020-05-27
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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
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Many wireless communications CHANNELs consist of multiple signal paths from the transmitter to receiver. This multiplicity of paths leads to a phenomenon known as multipath fading. The multiple paths are caused by the presence of objects in the physical environment that, through the mechanisms of propagation, alter the path of radiated energy. These objects are referred to as scatterers. In the past, researchers often looked at ways to mitigate multipath scattering, such as in diversity systems. Multiple-input, multiple-output (MIMO) systems, on the other hand, use multipath diversity to their advantage; a MIMO system has the ability to translate increased spatial diversity into increased channel capacity.
标签: Multiple-Output Multiple-Input Channel Models
上传时间: 2020-05-31
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Since the advent of optical communications, a great technological effort has been devoted to the exploitation of the huge bandwidth of optical fibers. Start- ing from a few Mb/s single channel systems, a fast and constant technological development has led to the actual 10 Gb/s per channel dense wavelength di- vision multiplexing (DWDM) systems, with dozens of CHANNELs on a single fiber. Transmitters and receivers are now ready for 40 Gb/s, whereas hundreds of CHANNELs can be simultaneously amplified by optical amplifiers.
标签: Communication Techniques Optical Theory and
上传时间: 2020-05-31
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Orthogonal frequency division multiplexing (OFDM) has been shown to be an effective technique to combat multipath fading in wireless CHANNELs. It has been and is going to be used in various wireless communication systems. This book gives a comprehensive introduction on the theory and practice of OFDM for wireless communications.
标签: Multiplexing Orthogonal Frequency Division
上传时间: 2020-05-31
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The investigation of the propagation channel is becoming more and more important in mod- ern wireless communication. The demand for spectral efficiency motivates exploitation of all CHANNELs that can possibly be used for communications. Nowadays, a common trend for designing physical layer algorithms is to adapt the transceiving strategy, either by maximizing the diversity gains or by utilizing the coherence of the CHANNELs to improve the signal-to-noise power ratio.
标签: Characterization Propagation Channel
上传时间: 2020-05-31
上传用户:shancjb