Results 271 to 280 of about 12,863 (308)

Co-channel interference reduction in Rayleigh fading channels

Digital Signal Processing, 2006
Abstract Interference can be a significant problem in loosely organized networks such as ad-hoc radio networks. One technique for dealing with interference is to attempt joint detection of all signals arriving at a node. Iterative algorithms based on the turbo-principle yield significant performance improvements when applied to this problem.
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Symbol-aided channel estimation with nonselective Rayleigh fading channels

Proceedings of ICC/SUPERCOMM'94 - 1994 International Conference on Communications, 1995
New algorithms are proposed to implement coherent detection of PSK signals transmitted over frequency-flat Rayleigh channels. Channel gain estimates are derived both from known symbols multiplexed with the data stream and from tentative data decisions. The performance of these algorithms is assessed by computer simulation with uncoded and trellis-coded
Aldo N. D'Andrea, Antonello Diglio, Umberto Mengali   +2 more
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Adaptive LDPC for Rayleigh fading channel

Proceedings. ISCC 2004. Ninth International Symposium on Computers And Communications (IEEE Cat. No.04TH8769), 2004
Two adaptive coded modulation schemes employing LDPC (low-density parity-check) code are proposed for Rayleigh fading channels. Scheme 1: we fix the code rate (rate=1/2), and only change the modulation methods according to the channel state, that is, during poor channel conditions, QPSK modulation is employed, as channel conditions improve, more ...
null Yuling Zhang, null Dongfeng Yuan, null Haigang Zhang   +2 more
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Analog joint source-channel coding in Rayleigh fading channels

2011 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), 2011
We consider discrete-time all-analog-processing joint source-channel coding, using non-linear spiral-like curves. We assume a Rayleigh channel, where the receiver may employ or not multiple antennas. Maximum Likelihood (ML) and Minimum Mean Square Error (MMSE) detection are considered.
Glauber Gomes de Oliveira Brante, Richard Demo Souza, Javier Garcia-Frias   +2 more
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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.
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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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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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Adaptive MIMO channel estimation for fast Rayleigh fading channels

IEEE 60th Vehicular Technology Conference, 2004. VTC2004-Fall. 2004, 2005
A novel adaptive channel estimation algorithm for fast fading channels is proposed. The algorithm is based on an adaptive multi-rate filter bank structure. Unlike conventional MIMO systems, where a block fading channel model is typically assumed, a continuous fading model is considered in order to deal with fast fading in MIMO systems.
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Channel reliability metrics for flat Rayleigh fading channels without channel state information

SympoTIC '04. Joint 1st Workshop on Mobile Future & Symposium on Trends In Communications (IEEE Cat. No.04EX877), 2005
In this work, iterative decoding of block turbo codes (BTCs) over flat Rayleigh fading channels is considered. The signal is modulated using binary phase shift keying (BPSK) and coherently detected. An exact channel reliability metric that should be passed to the iterative decoder to achieve optimum performance, when no channel state information (CSI ...
A. Shaheem, M. Caldera, H.-R. Zepernick
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