Results 191 to 200 of about 1,330,151 (239)

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 ...
Yuling Zhang, Dongfeng Yuan, Haigang Zhang   +2 more
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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 J. Salomon, Ofer Amrani
openaire   +1 more source

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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LDPC coded modulation for Rayleigh fading channels

2012 International Conference on Wireless Communications and Signal Processing (WCSP), 2012
This paper presents a novel scheme of low-density-parity-check (LDPC) coded modulation system called bit-expand-interleaved coded modulation with iterative decoding and demapping (BEICM-ID) over Rayleigh fading channels. In traditional bit-interleaved coded modulation (BICM) schemes and its iterative version, BICM-ID, each bit node is mapped into one ...
Jintao Li, Yibin Yang, Hui Yu 0002, Yunfeng Guan 0001   +3 more
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Compressive Sensing for the Capacity of a Rayleigh Fading Channel

2011 IEEE International Conference on Communications (ICC), 2011
A given objective function, $I(p_X(x))$, is to be maximized over the argument $p_X(x)$, where $p_X(x)$ is a continuous function of $x \in R^1$. Rather than optimizing $I(p_X(x))$ over the domain of functions, where the optimal solution $p_X^*(x)$ is non-zero only at a few but unknown discrete points $x \in \{x_1 , x_2 , \ldots , x_S \} $, is it ...
Jocelyn Aulin, Djordje Jeremic
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Exact Coherence Bandwidth of Rayleigh Fading Channels

2007 IEEE 18th International Symposium on Personal, Indoor and Mobile Radio Communications, 2007
Determination of the coherence bandwidth for multipath fading channels is of great importance for wireless systems design. However, the calculation of the coherence bandwidth so far has relied on an empirical formula. In this paper, we derive an exact coherence bandwidth formula for Rayleigh fading channels. The use of the new formula is illustrated by
Keith Q. T. Zhang, Shenghui Song 0001
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GQR models for multipath Rayleigh fading channels

IEEE Journal on Selected Areas in Communications, 2001
In this paper, reduced complexity statistical models for the representation of wide sense stationary-uncorrelated scattering doubly selective fading channels are developed. Their derivation is based on the evaluation of Fourier integrals by means of Gaussian quadrature rules.
CHIAVACCINI, Eugenio, VITETTA, Giorgio Matteo   +1 more
openaire   +1 more source

TCM and diversity in a Rayleigh fading channel

5th IEEE International Symposium on Personal, Indoor and Mobile Radio Communications, Wireless Networks - Catching the Mobile Future., 2002
The performance of trellis coded 8-PSK with diversity is examined in the paper. The "pragmatic" approach to TCM is assumed, where the code is constructed using a common a rate 1/2 constraint length 7 codec. Using diversity in the form of soft symbol combining in a concatenated TCM/diversity modulation, a performance improvement of about 2 to 3 dB was ...
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Multilevel block codes for Rayleigh-fading channels

IEEE Transactions on Communications, 1995
Summary: New multilevel block codes for Rayleigh-fading channels are presented. At high signal-to-noise ratios, the proposed block codes can achieve better bit error performance over TCM codes, optimum for fading channels, with comparable decoder complexity and bandwidth efficiency.
Lin Zhang 0002, Branka Vucetic
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Optimized Selection Diversity for Rayleigh Fading Channels

IEEE Transactions on Communications, 1982
This paper considers the choice of the number of diversity branches for minimizing the bit error rate of a selection diversity system using noncoherent binary frequency-shift keying modulation for transmission over a Rayleigh fading Gaussian channel. An exact expression for the optimum number of branches, L_{sel}^{\ast} , is given.
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