Results 221 to 230 of about 45,199 (262)

Product Construction of Codes for Rayleigh-Fading Channels

IEEE Transactions on Information Theory, 2006
Coded modulation scheme of high coding gain is presented for slowly-varying flat fading channels. The scheme introduces a product construction employing two types of codes: "standard" good codes and codes that are more suitable for the fading channel. Short-blocklength codes of unique features are thus obtained.
Amir Salomon, Ofer Amrani
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Random Power Control for Uncorrelated Rayleigh Fading Channels

2007 IEEE International Conference on Signal Processing and Communications, 2007
When the channel measurement update rate is very slow compared to the channel fluctuations, the performance of conventional power control algorithms is greatly reduced. In this paper we introduce novel method to update the transmit power in such extreme situations.
Mohammed Elmusrati, Naser Tarhuni, Riku Jantti   +2 more
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Statistics of Sampled Rayleigh Fading

1988
Abstract : This report addresses the requirements on the length and resolution of realizations of sampled Rayleigh fading used in simulation or hardware testing of communications links. Measurements of the cumulative distribution, mean fade duration, and mean fade separation are compared to ensemble values.
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Transmit diversity for arrays with correlated Rayleigh fading

Conference Record of the Thirty-Fourth Asilomar Conference on Signals, Systems and Computers (Cat. No.00CH37154), 2002
Transmit diversity is usually presented for the case of independently faded channels. In this paper the structure of a linear transmitter that can be optimized for a Rayleigh-fading environment in which the fading may be correlated is derived. The transmitter achieves the best mix of array gain-obtained by beamforming, and diversity gain-obtained by ...
C. van Rensburg, B. Friedlander
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Fade margins for minimum duration outages in lognormal shadow fading and Rayleigh fading

Conference Record of the Thirty-First Asilomar Conference on Signals, Systems and Computers (Cat. No.97CB36136), 2002
Minimum duration outages have been used to characterize time-dependent performance in analysis of quantities such as average duration of an outage, the probability of outage, and the frequency of outage, in lognormal shadow fading (Mandayam et al., 1996) and Rayleigh fading (Lai and Mandayam, 1997), respectively.
null Jie Lai, N.B. Mandayam
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Packet Radio Performance Over Slow Rayleigh Fading Channels

IEEE Transactions on Communications, 1980
Expressions for the throughput and average packet delay for a Pure-ALOHA single-hop packet radio system operating in slow Rayleigh fading are derived. For noncoherent frequency-shift-keying (NCFSK), an exact closed form expression is presented. For coherent phase-shift-keying (CPSK) an excellent approximation for large packet sizes is derived.
Roberts, James A., Healy, Timothy J.
openaire   +2 more sources

Switched-diversity FSK in frequency-selective Rayleigh fading

33rd IEEE Vehicular Technology Conference, 1983
This paper presents the measured performance of a 64 kbit/s switched-diversity FSK receiver subjected to simulated frequency-selective Rayleigh fading. The single receiver input is switched between two, three, or four uncorrelated Rayleigh-fading signals whenever the instantaneous receiver output falls below a threshold.
H. Arnold, W. Bodtmann
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Distributed jammer performance in Rayleigh fading

MILCOM 2002. Proceedings, 2003
A distributed jammer is a set of small jamming transmitters distributed over a region to disrupt tactical communications. Propagation losses experienced by terrestrial jammers will be comparable to losses seen by the target radio links, with multipath fading, and power failing off faster than 1/r/sup 2/.
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On SIR fade statistics in Rayleigh-lognormal channels

2002 IEEE International Conference on Communications. Conference Proceedings. ICC 2002 (Cat. No.02CH37333), 2003
An analytical approach to derive the level crossing rate (LCR) and the average fade duration (AFD) for the signal-to-interference ratio (SIR) in a mobile radio system is proposed. The channel model is characterized by a log-normal shadowing component and a Rayleigh fast fading component on the useful link and on interfering links.
GRAZIOSI, FABIO, SANTUCCI, FORTUNATO
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Generation of correlated Rayleigh fading envelopes

IEEE Communications Letters, 1999
A previous technique for generating correlated Rayleigh envelopes is generalized and physically interpreted to model specified propagation delay spread and frequency separation. Two accurate closed-form expressions that give explicitly the squared magnitude of the complex Gaussian cross-correlation coefficient in terms of the real envelope cross ...
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