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Fading distribution

About: Fading distribution is a research topic. Over the lifetime, 5732 publications have been published within this topic receiving 114193 citations.


Papers
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Proceedings ArticleDOI
21 Mar 2007
TL;DR: In this article, an overview of how measurements in reverberation chambers can be used to characterize the performance of small antennas and wireless terminals for mobile communications in environments with Rayleigh fading.
Abstract: The paper gives an overview of how measurements in reverberation chambers can be used to characterize the performance of small antennas and wireless terminals for mobile communications in environments with Rayleigh fading. The measurement capabilities include radiation efficiency, radiated power, diversity gain, MIMO system capacity and receiver sensitivity. In the latter case the reverberation chamber enable fast measurements of bit error rate (BER) and frame error rate (FER), and thereby total isotropic sensitivity (TIS). In addition, the terminals can be tested under realistic and continuous fading very similar to what is present in urban and indoor environments, referred to as average fading sensitivity (AFS). The chamber is the only known measurement instrument for directly measuring diversity gain and channel capacity; the alternative being to drive measurement instruments around in an actual urban environment. The measurements can fast and easily be performed for different talk positions relative to a head phantom.

31 citations

Proceedings ArticleDOI
J.M. Holtzman1
14 Jun 1992
TL;DR: The author exploits the information in signal strength measurements to improve the quality of the handoff decisions in cellular systems using the maximum Doppler frequency, the key to the tradeoff.
Abstract: The author exploits the information in signal strength measurements to improve the quality of the handoff decisions in cellular systems. As a vehicle moves, the signal strength changes due to distance from the base station, slow fading, and fast fading. The fluctuations due to slow and fast fading are usually considered as noise in this decision making process. This leads to a tradeoff problem for the averaging interval for the signal strength measurements. If the interval is too short, the fading fluctuations are not sufficiently smoothed out. If the interval is too long, the handoff mechanism is too sluggish. By considering this tradeoff, a method is presented to adaptively change the averaging interval. The method is based on estimating the maximum Doppler frequency, the key to the tradeoff. >

31 citations

Journal ArticleDOI
TL;DR: Numerical results are graphically presented to show the effects of various system parameters to the system performance, as well as the enhancement due to use of the combination of micro- and macrodiversity.
Abstract: In this paper, the performance of wireless system employing microdiversity to mitigate the effects of short-term fading and macrodiversity to reduce long-term fading (shadowing) effects is studied. The system model assumes implementation of maximal-ratio combining (MRC) at the microlevel and selection combining (SC) at the macrolevel. The received signal envelope follows a Rician distribution and it also suffers gamma shadowing. Novel expressions for the probability density function (PDF), cumulative distribution function (CDF), and moment-generating function (MGF) of the output signal-to-noise ratio (SNR) are obtained. Several useful performance criteria, such as the moments of the output SNR and outage probability are analytically derived. Moreover, the average bit error probability (ABEP) for noncoherent binary differential phase-shift keying (BDPSK) is calculated using the MGF based approach while the ABEP for coherent binary phase-shift keying (BPSK) is studied by averaging the conditional bit error probability over the PDF. Numerical results are graphically presented to show the effects of various system parameters to the system performance, as well as the enhancement due to use of the combination of micro- and macrodiversity. Some of numerical results are complemented by equivalent computer simulated results which validate the accuracy of the proposed analysis. The agreement between the Rician-gamma and Rician-lognormal fading model is also established.

31 citations

Journal ArticleDOI
TL;DR: The performances of several diversity schemes, including a practical variation of maximal-ratio combining that does not require signal-to-noise ratios at different antennas, equal-gain combining, and selection combining, are compared analytically for an interference-limited environment in a Rayleigh fading channel.
Abstract: Space diversity is an effective method to combat fading and cochannel interference (CCI) in wireless systems. In this paper, outage performances of several diversity schemes, including a practical variation of maximal-ratio combining that does not require signal-to-noise ratios at different antennas, equal-gain combining, and selection combining, are compared analytically for an interference-limited environment in a Rayleigh fading channel. Our analysis provides insight into the performance of diversity schemes in the presence of CCI as well as assesses the impact of cochannel interferer power distributions.

31 citations


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Performance
Metrics
No. of papers in the topic in previous years
YearPapers
202322
202270
202123
202022
201920
201837