The Experts below are selected from a list of 25782 Experts worldwide ranked by ideXlab platform
Shraga I Bross - One of the best experts on this subject based on the ideXlab platform.
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on the discrete memoryless partially cooperative broadcast Relay Channel
International Symposium on Information Theory, 2007Co-Authors: Shraga I BrossAbstract:A partially cooperative Relay broadcast Channel is a network with one source node and two destination nodes wherein destination 1 acts as a Relay to assist destination 2. We derive two inner bounds on the rate region of this model. The first inner bound is based on the Cover-El Gamal generalized strategy for the original Relay Channel, while the second inner bound is based on the strategy proposed by Chong-Motani-Garg, for the Relay Channel, which combines backward decoding and simultaneous decoding. Both rate regions subsume the inner bound reported by Liang and Kramer which is based just on the decode-and-forward strategy for the common message.
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achievable rates for the discrete memoryless Relay Channel with partial feedback configurations
IEEE Transactions on Information Theory, 2006Co-Authors: Y Gabbai, Shraga I BrossAbstract:Achievable rates over the discrete memoryless Relay Channel with partial feedback configurations are proposed. Specifically, we consider partial feedback from the receiver to the sender as well as partial feedback from the Relay to the sender. These achievable rates are calculated for the general Gaussian and the Z Relay Channels and are shown to improve on the known one-way achievable rates
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a converse result for the discrete memoryless Relay Channel with Relay transmitter feedback
IEEE Transactions on Information Theory, 2006Co-Authors: Shraga I BrossAbstract:A converse result is proved for the discrete memoryless Relay Channel in the presence of Relay-transmitter causal feedback. The result subsumes the Cover-El Gamal max-flow min-cut upper bound on the capacity of the one-way Relay Channel, and it is used to establish the partial feedback capacity of the semideterministic Relay Channel
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on the discrete memoryless Relay Channel with Relay transmitter feedback
International Symposium on Information Theory, 2006Co-Authors: Y Gabbai, Shraga I BrossAbstract:A coding technique is proposed for the discrete memoryless Relay Channel with noiseless feedback from Relay to transmitter. The achievability result we obtain is an analogue to a result proposed by Cover and El Gamal that combines cooperation and transmission of compressed data.
Raymond Knopp - One of the best experts on this subject based on the ideXlab platform.
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On the Gaussian Half-Duplex Relay Channel
IEEE Transactions on Information Theory, 2014Co-Authors: Martina Cardone, Raymond Knopp, Daniela Tuninetti, Umer SalimAbstract:This paper considers the Gaussian half-duplex Relay Channel (G-HD-RC): a Channel model where a source transmits a message to a destination with the help of a Relay that cannot transmit and receive at the same time. It is shown that the cut-set upper bound on the capacity can be achieved to within a constant gap, regardless of the actual value of the Channel parameters, by either partial-decode-and-forward or compress-and-forward. The performance of these coding strategies is evaluated with both random and deterministic switch at the Relay. Numerical evaluations show that the actual gap is less than what analytically obtained, and that random switch achieves higher rates than deterministic switch. As a result of this analysis, the generalized degrees-of-freedom of the G-HD-RC is exactly characterized for this Channel. In order to get insights into practical schemes for the G-HD-RC that are less complex than partial-decode-and-forward or compress-and-forward, the exact capacity of the linear deterministic approximation (LDA) of the G-HD-RC at high signal-to-noise-ratio is determined. It is shown that random switch and correlated nonuniform inputs bits are optimal for the LDA. It is then demonstrated that deterministic switch is to within one bit from the capacity. This latter scheme is translated into a coding strategy for the original G-HD-RC and its optimality to within a constant gap is proved. The gap attained by this scheme is larger than that of partial-decode-and-forward, thereby pointing to an interesting practical tradeoff between gap to capacity and complexity.
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The capacity to within a constant gap of the Gaussian half-duplex Relay Channel
2013 IEEE International Symposium on Information Theory, 2013Co-Authors: Martina Cardone, Raymond Knopp, Daniela Tuninetti, Umer SalimAbstract:This paper studies the Gaussian half duplex Relay Channel, where the Relay node can not transmit and receive at the same time. The main contribution lies in showing that both Partial-Decode-Forward and Compress-Forward achieve the CutSet upper bound to within a constant gap regardless of the Channel parameters. This provides a closed form characterization of the Generalized Degrees-of-Freedom (gDoF) of the Channel, which for certain Channel parameters is strictly smaller than the gDoF of the full duplex Channel. Half duplex Channels can convey information through the random switch between the receive and retransmit phases; this work shows numerically that random switch achieves larger rates compared to deterministic switch, which is usually considered in the literature.
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Interference Relay Channel in 4G wireless networks
2012 IEEE Wireless Communications and Networking Conference (WCNC), 2012Co-Authors: Erhan Yilmaz, David Gesbert, Raymond KnoppAbstract:In the next generation cellular systems, such as LTE-A (Release 10 and beyond), Relay node (RN) deployment has been adopted due to its potentials in enlarging coverage and increasing system throughput, even with primitive Relaying functionalities. For example, in LTE-A Release 10 only Type-I (non-transparent) RNs are considered wherein no cooperative transmission to the Donor evolved-NodeBs (DeNBs) is allowed. In this paper, we would like to add more functionalities to the RNs and see the advantages of using cooperative Relaying, i.e., Type-II RNs. In particular, we study an interference Relay Channel (IRC) consisting of two single-antenna transmitter-receiver pairs and a shared multiple-antenna RN, which is exploited in a way that interferer's signal components at each receiver node are eliminated. Specifically, at the RN a transmit filtering is performed such that the compound received signal at each user equipment (UE) has a structure similar to the receiver structure for Alamouti's space-time coding [1]. We also show that it is not always required to have more complex receiver structure at the RN in order to achieve better spectral efficiencies.
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Multi-pair two-way Relay Channel with multiple antenna Relay station
IEEE International Conference on Communications, 2010Co-Authors: Erhan Yilmaz, Randa Zakhour, David Gesbert, Raymond KnoppAbstract:We consider a multi-pair two-way Relay Channel (TWRC) where the single-antenna mobile terminals (MT) on each pair seek to communicate, and can do so, via a common multiple antenna Relay station (RS). In the multi-pair TWRC, the main bottleneck on system performance is the interference seen by each MT due to the other communicating MT pairs. In this paper, we try to tackle this problem in the spatial domain by using multiple antennas at the RS. Considering Amplify-and-Forward (AF) and Quantize-and-Forward (QF) Relaying strategies, different transmit/receive beamforming schemes at the RS are proposed. We compare our proposed schemes to each other and to the Decode-and-Forward (DF) Relaying strategy with achievable sum rate taken as a performance metric and show that in a wide range of signal-to-noise ratio (SNR) our schemes outperform the DF Relaying strategy.
Umer Salim - One of the best experts on this subject based on the ideXlab platform.
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On the Gaussian Half-Duplex Relay Channel
IEEE Transactions on Information Theory, 2014Co-Authors: Martina Cardone, Raymond Knopp, Daniela Tuninetti, Umer SalimAbstract:This paper considers the Gaussian half-duplex Relay Channel (G-HD-RC): a Channel model where a source transmits a message to a destination with the help of a Relay that cannot transmit and receive at the same time. It is shown that the cut-set upper bound on the capacity can be achieved to within a constant gap, regardless of the actual value of the Channel parameters, by either partial-decode-and-forward or compress-and-forward. The performance of these coding strategies is evaluated with both random and deterministic switch at the Relay. Numerical evaluations show that the actual gap is less than what analytically obtained, and that random switch achieves higher rates than deterministic switch. As a result of this analysis, the generalized degrees-of-freedom of the G-HD-RC is exactly characterized for this Channel. In order to get insights into practical schemes for the G-HD-RC that are less complex than partial-decode-and-forward or compress-and-forward, the exact capacity of the linear deterministic approximation (LDA) of the G-HD-RC at high signal-to-noise-ratio is determined. It is shown that random switch and correlated nonuniform inputs bits are optimal for the LDA. It is then demonstrated that deterministic switch is to within one bit from the capacity. This latter scheme is translated into a coding strategy for the original G-HD-RC and its optimality to within a constant gap is proved. The gap attained by this scheme is larger than that of partial-decode-and-forward, thereby pointing to an interesting practical tradeoff between gap to capacity and complexity.
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The capacity to within a constant gap of the Gaussian half-duplex Relay Channel
2013 IEEE International Symposium on Information Theory, 2013Co-Authors: Martina Cardone, Raymond Knopp, Daniela Tuninetti, Umer SalimAbstract:This paper studies the Gaussian half duplex Relay Channel, where the Relay node can not transmit and receive at the same time. The main contribution lies in showing that both Partial-Decode-Forward and Compress-Forward achieve the CutSet upper bound to within a constant gap regardless of the Channel parameters. This provides a closed form characterization of the Generalized Degrees-of-Freedom (gDoF) of the Channel, which for certain Channel parameters is strictly smaller than the gDoF of the full duplex Channel. Half duplex Channels can convey information through the random switch between the receive and retransmit phases; this work shows numerically that random switch achieves larger rates compared to deterministic switch, which is usually considered in the literature.
Patrick Mitran - One of the best experts on this subject based on the ideXlab platform.
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time asynchronous gaussian multiple access Relay Channel with correlated sources
IEEE Transactions on Information Theory, 2016Co-Authors: Hamidreza Ebrahimzadeh Saffar, Masoud Badiei Khuzani, Patrick MitranAbstract:We study the transmission of a set of correlated sources ${(U_{1},\ldots ,U_{K})}$ over a Gaussian multiple access Relay Channel with time asynchronism between the encoders. We assume that the maximum possible offset $ { \mathsf {d_{max}}(n)}$ between the transmitters grows without bound as the block length ${n \rightarrow \infty }$ , while the relative ratio $ {{ \mathsf {d_{max}}(n) / n}}$ of the maximum possible offset to the block length asymptotically vanishes. For such a joint source-Channel coding problem and under specific gain conditions, we derive necessary and sufficient conditions for reliable communications and show that separate source and Channel coding achieves optimal performance. In particular, we first derive a general outer bound on the source entropy content for all Channel gains as our main result. Then, using Slepian–Wolf source coding combined with the Channel coding scheme on top of block Markov coding, we show that the thus achieved inner bound matches the outer bound. As a corollary, we also address the problem of sending a pair of correlated sources over a two-user interference Channel in the same context.
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time asynchronous gaussian multiple access Relay Channel with correlated sources
arXiv: Information Theory, 2014Co-Authors: Hamidreza Ebrahimzadeh Saffar, Masoud Badiei Khuzani, Patrick MitranAbstract:We study the transmission of a set of correlated sources $(U_1,\cdots,U_K)$ over a Gaussian multiple access Relay Channel with time asynchronism between the encoders. We assume that the maximum possible offset ${\mathsf{d_{max}}}(n)$ between the transmitters grows without bound as the block length $n \rightarrow \infty$ while the relative ratio ${{\mathsf{d_{max}}}(n) / n}$ of the maximum possible offset to the block length asymptotically vanishes. For such a joint source-Channel coding problem, and under specific gain conditions, we derive necessary and sufficient conditions for reliable communications and show that separate source and Channel coding achieves optimal performance. In particular, we first derive a general outer bound on the source entropy content for all Channel gains as our main result. Then, using Slepian-Wolf source coding combined with the Channel coding scheme introduced in \cite{Cover_McEliece:81} on top of block Markov coding, we show that the thus achieved inner bound matches the outer bound. Consequently, as a corollary, we also address the problem of sending a pair of correlated sources over a two user interference Channel in the same context.
Martina Cardone - One of the best experts on this subject based on the ideXlab platform.
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On the Gaussian Half-Duplex Relay Channel
IEEE Transactions on Information Theory, 2014Co-Authors: Martina Cardone, Raymond Knopp, Daniela Tuninetti, Umer SalimAbstract:This paper considers the Gaussian half-duplex Relay Channel (G-HD-RC): a Channel model where a source transmits a message to a destination with the help of a Relay that cannot transmit and receive at the same time. It is shown that the cut-set upper bound on the capacity can be achieved to within a constant gap, regardless of the actual value of the Channel parameters, by either partial-decode-and-forward or compress-and-forward. The performance of these coding strategies is evaluated with both random and deterministic switch at the Relay. Numerical evaluations show that the actual gap is less than what analytically obtained, and that random switch achieves higher rates than deterministic switch. As a result of this analysis, the generalized degrees-of-freedom of the G-HD-RC is exactly characterized for this Channel. In order to get insights into practical schemes for the G-HD-RC that are less complex than partial-decode-and-forward or compress-and-forward, the exact capacity of the linear deterministic approximation (LDA) of the G-HD-RC at high signal-to-noise-ratio is determined. It is shown that random switch and correlated nonuniform inputs bits are optimal for the LDA. It is then demonstrated that deterministic switch is to within one bit from the capacity. This latter scheme is translated into a coding strategy for the original G-HD-RC and its optimality to within a constant gap is proved. The gap attained by this scheme is larger than that of partial-decode-and-forward, thereby pointing to an interesting practical tradeoff between gap to capacity and complexity.
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The capacity to within a constant gap of the Gaussian half-duplex Relay Channel
2013 IEEE International Symposium on Information Theory, 2013Co-Authors: Martina Cardone, Raymond Knopp, Daniela Tuninetti, Umer SalimAbstract:This paper studies the Gaussian half duplex Relay Channel, where the Relay node can not transmit and receive at the same time. The main contribution lies in showing that both Partial-Decode-Forward and Compress-Forward achieve the CutSet upper bound to within a constant gap regardless of the Channel parameters. This provides a closed form characterization of the Generalized Degrees-of-Freedom (gDoF) of the Channel, which for certain Channel parameters is strictly smaller than the gDoF of the full duplex Channel. Half duplex Channels can convey information through the random switch between the receive and retransmit phases; this work shows numerically that random switch achieves larger rates compared to deterministic switch, which is usually considered in the literature.
