The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Pascal Scalart - One of the best experts on this subject based on the ideXlab platform.
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General Minimum Euclidean Distance-based precoder for MIMO wireless systems
EURASIP Journal on Advances in Signal Processing, 2013Co-Authors: Quoc-tuong Ngo, Olivier Berder, Pascal ScalartAbstract:In this article, we investigate the linear precoder based on the maximization of the Minimum Euclidean Distance between two received data vectors. This new precoding matrix is expressed as the product of a power allocation matrix and an input-shaping matrix. The input-shaping matrix is selected as a normalized discrete Fourier transform-matrix, and the optimal power allocation depends on the channel characteristics. For each number of available datastreams, we propose a general form of the optimized precoding matrix. These forms are suitable for different transmit channels and especially for all rectangular quadrature amplitude modulation modulations. We show, in the simulation results, that the proposed precoder provides a significant improvement in terms of bit error rate performance compared to other traditional precoding strategies.
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Minimum Euclidean Distance based precoders for mimo systems using rectangular qam modulations
IEEE Transactions on Signal Processing, 2012Co-Authors: Quoc-tuong Ngo, Olivier Berder, Pascal ScalartAbstract:From the feedback of the channel state information (CSI), precoding techniques improve the performance of multiple-input multiple-output (MIMO) systems by optimizing various criteria. In this correspondence, an efficient precoder that maximizes the Minimum Distance (dmin) of two received vectors is studied. This criterion leads to a nondiagonal precoding scheme and allows achieving a full diversity order. However, the optimized solution for MIMO systems using a high-order QAM modulation is rather complex and changes for different constellations. Therefore, we propose herein a general form of Minimum Euclidean Distance based precoders for all rectangular QAM modulations. It is shown that the new solution optimizes the Distance dmin for small and large dispersive channels.
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Minimum Euclidean Distance-Based Precoding for Three-Dimensional Multiple Input Multiple Output Spatial Multiplexing Systems
IEEE Transactions on Wireless Communications, 2012Co-Authors: Quoc-tuong Ngo, Olivier Berder, Pascal ScalartAbstract:Through a feedback link, the channel state information acquired at the receiver is known at the transmitter and MIMO precoding techniques can be applied according to various criteria. In this paper, an efficient linear precoder based on the maximization of the Minimum Euclidean Distance between two received data vectors for three data-stream MIMO spatial multiplexing systems is proposed. By using a singular value decomposition, the precoding matrix can be parameterized as the product of a power allocation matrix and an input shaper matrix. According to this representation, the optimal precoders are proposed for the case of three independent data-streams. Simulation results over Rayleigh fading channels show considerable bit-error-rate improvement with the proposed solution in comparison with other precoding strategies.
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3 d Minimum Euclidean Distance based sub optimal precoder for mimo spatial multiplexing systems
International Conference on Communications, 2010Co-Authors: Quoc-tuong Ngo, O Berder, Pascal ScalartAbstract:This paper proposes an efficient sub-optimal MIMO linear precoder based on the maximization of Minimum Distance for three virtual suchannels. A new virtual MIMO channel representation with two channel angles allows the parameterization of the linear precoder and the optimization of the Distance between signal points at the received constellation. To illustrate the optimization process, a precoder is derived for BPSK and QPSK modulation following the max-SNR approach, which consists in pouring power only on the most favored virtual sub-channel. Simulation results over a Rayleigh channel confirm the interest of this new precoder in terms of bit-error-rate.
Quoc-tuong Ngo - One of the best experts on this subject based on the ideXlab platform.
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General Minimum Euclidean Distance-based precoder for MIMO wireless systems
EURASIP Journal on Advances in Signal Processing, 2013Co-Authors: Quoc-tuong Ngo, Olivier Berder, Pascal ScalartAbstract:In this article, we investigate the linear precoder based on the maximization of the Minimum Euclidean Distance between two received data vectors. This new precoding matrix is expressed as the product of a power allocation matrix and an input-shaping matrix. The input-shaping matrix is selected as a normalized discrete Fourier transform-matrix, and the optimal power allocation depends on the channel characteristics. For each number of available datastreams, we propose a general form of the optimized precoding matrix. These forms are suitable for different transmit channels and especially for all rectangular quadrature amplitude modulation modulations. We show, in the simulation results, that the proposed precoder provides a significant improvement in terms of bit error rate performance compared to other traditional precoding strategies.
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Minimum Euclidean Distance based precoders for mimo systems using rectangular qam modulations
IEEE Transactions on Signal Processing, 2012Co-Authors: Quoc-tuong Ngo, Olivier Berder, Pascal ScalartAbstract:From the feedback of the channel state information (CSI), precoding techniques improve the performance of multiple-input multiple-output (MIMO) systems by optimizing various criteria. In this correspondence, an efficient precoder that maximizes the Minimum Distance (dmin) of two received vectors is studied. This criterion leads to a nondiagonal precoding scheme and allows achieving a full diversity order. However, the optimized solution for MIMO systems using a high-order QAM modulation is rather complex and changes for different constellations. Therefore, we propose herein a general form of Minimum Euclidean Distance based precoders for all rectangular QAM modulations. It is shown that the new solution optimizes the Distance dmin for small and large dispersive channels.
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Minimum Euclidean Distance-Based Precoding for Three-Dimensional Multiple Input Multiple Output Spatial Multiplexing Systems
IEEE Transactions on Wireless Communications, 2012Co-Authors: Quoc-tuong Ngo, Olivier Berder, Pascal ScalartAbstract:Through a feedback link, the channel state information acquired at the receiver is known at the transmitter and MIMO precoding techniques can be applied according to various criteria. In this paper, an efficient linear precoder based on the maximization of the Minimum Euclidean Distance between two received data vectors for three data-stream MIMO spatial multiplexing systems is proposed. By using a singular value decomposition, the precoding matrix can be parameterized as the product of a power allocation matrix and an input shaper matrix. According to this representation, the optimal precoders are proposed for the case of three independent data-streams. Simulation results over Rayleigh fading channels show considerable bit-error-rate improvement with the proposed solution in comparison with other precoding strategies.
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3 d Minimum Euclidean Distance based sub optimal precoder for mimo spatial multiplexing systems
International Conference on Communications, 2010Co-Authors: Quoc-tuong Ngo, O Berder, Pascal ScalartAbstract:This paper proposes an efficient sub-optimal MIMO linear precoder based on the maximization of Minimum Distance for three virtual suchannels. A new virtual MIMO channel representation with two channel angles allows the parameterization of the linear precoder and the optimization of the Distance between signal points at the received constellation. To illustrate the optimization process, a precoder is derived for BPSK and QPSK modulation following the max-SNR approach, which consists in pouring power only on the most favored virtual sub-channel. Simulation results over a Rayleigh channel confirm the interest of this new precoder in terms of bit-error-rate.
Olivier Berder - One of the best experts on this subject based on the ideXlab platform.
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Distributed Minimum Euclidean Distance based precoding for wireless sensor network
2015 International Conference on Computing Networking and Communications (ICNC), 2015Co-Authors: Viethoa Nguyen, Charlotte Langlais, Olivier Berder, Baptiste VrigneauAbstract:Among various cooperative techniques aiming to reduce power consumption for Wireless Sensor Network (WSN), we present a new approach, named distributed max-dmin precoding (DMP). This protocol is based on the deployment of a virtual 2×2 max-dmin precoding over one source, one forwarding relay, both equipped with one antenna and a destination involving 2 antennas. In this context, two kinds of relaying, amplify and forward or decode and forward protocols, are investigated. The performance evaluation in terms of Bit-Error-Rate (BER) and energy efficiency will be compared with non cooperative techniques (SISO, SIMO) and the distributed space time block code (STBC) scheme. Our investigations show that the DMP takes the advantage in terms of energy efficiency from medium transmission Distances.
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General Minimum Euclidean Distance-based precoder for MIMO wireless systems
EURASIP Journal on Advances in Signal Processing, 2013Co-Authors: Quoc-tuong Ngo, Olivier Berder, Pascal ScalartAbstract:In this article, we investigate the linear precoder based on the maximization of the Minimum Euclidean Distance between two received data vectors. This new precoding matrix is expressed as the product of a power allocation matrix and an input-shaping matrix. The input-shaping matrix is selected as a normalized discrete Fourier transform-matrix, and the optimal power allocation depends on the channel characteristics. For each number of available datastreams, we propose a general form of the optimized precoding matrix. These forms are suitable for different transmit channels and especially for all rectangular quadrature amplitude modulation modulations. We show, in the simulation results, that the proposed precoder provides a significant improvement in terms of bit error rate performance compared to other traditional precoding strategies.
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Minimum Euclidean Distance based precoders for mimo systems using rectangular qam modulations
IEEE Transactions on Signal Processing, 2012Co-Authors: Quoc-tuong Ngo, Olivier Berder, Pascal ScalartAbstract:From the feedback of the channel state information (CSI), precoding techniques improve the performance of multiple-input multiple-output (MIMO) systems by optimizing various criteria. In this correspondence, an efficient precoder that maximizes the Minimum Distance (dmin) of two received vectors is studied. This criterion leads to a nondiagonal precoding scheme and allows achieving a full diversity order. However, the optimized solution for MIMO systems using a high-order QAM modulation is rather complex and changes for different constellations. Therefore, we propose herein a general form of Minimum Euclidean Distance based precoders for all rectangular QAM modulations. It is shown that the new solution optimizes the Distance dmin for small and large dispersive channels.
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Minimum Euclidean Distance-Based Precoding for Three-Dimensional Multiple Input Multiple Output Spatial Multiplexing Systems
IEEE Transactions on Wireless Communications, 2012Co-Authors: Quoc-tuong Ngo, Olivier Berder, Pascal ScalartAbstract:Through a feedback link, the channel state information acquired at the receiver is known at the transmitter and MIMO precoding techniques can be applied according to various criteria. In this paper, an efficient linear precoder based on the maximization of the Minimum Euclidean Distance between two received data vectors for three data-stream MIMO spatial multiplexing systems is proposed. By using a singular value decomposition, the precoding matrix can be parameterized as the product of a power allocation matrix and an input shaper matrix. According to this representation, the optimal precoders are proposed for the case of three independent data-streams. Simulation results over Rayleigh fading channels show considerable bit-error-rate improvement with the proposed solution in comparison with other precoding strategies.
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optimal Minimum Distance based precoder for mimo spatial multiplexing systems
IEEE Transactions on Signal Processing, 2004Co-Authors: Ludovic Collin, Olivier Berder, P Rostaing, Gilles BurelAbstract:We describe a new precoder based on optimization of the Minimum Euclidean Distance d/sub min/ between signal points at the receiver side and for use in multiple-input multiple-output (MIMO) spatial multiplexing systems. Assuming that channel state information (CSI) can be made available at the transmitter, the three steps ( noise whitening, channel diagonalization and dimension reduction), which are currently used in investigations on MIMO systems, are performed. Thanks to this representation, an optimal d/sub min/ precoder is derived in the case of two different transmitted data streams. For quadrature phase-shift keying (QPSK) modulation, a numerical approach shows that the precoder design depends on the channel characteristics. Comparisons with maximum signal-to-noise ratio (SNR) strategy and other precoders based on criteria, such as water-filling (WF), Minimum mean square error (MMSE), and maximization of the Minimum singular value of the global channel matrix, are performed to illustrate the significant bit-error-rate (BER) improvement of the proposed precoder.
Dzevdan Kapetanovic - One of the best experts on this subject based on the ideXlab platform.
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Construction of Minimum Euclidean Distance MIMO Precoders and Their Lattice Classifications
IEEE Transactions on Signal Processing, 2012Co-Authors: Dzevdan Kapetanovic, Fredrik Rusek, Traian E. Abrudan, Visa KoivunenAbstract:This correspondence deals with the construction of Minimum Euclidean Distance precoders for multiple-input multiple-output (MIMO) systems with up to four transmit antennas. By making use of a state-of-the-art technique for optimization over the unitary group, we can numerically optimize the MIMO precoders. The correspondence then proceeds by identifying the obtained precoders as well-known lattices (square Z2, Schläfli D4, D6, Gosset E8). With three transmit antennas, the results are slightly different compared with other numbers of transmit antennas since the obtained precoder is not an instance of the densest 6-dimensional lattice. The overall conclusions of the correspondence are that the found precoders for MIMO transmission are highly structured and that, even with small constellations, lattice theory can be used for the design of MIMO precoders.
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design of close to optimal Euclidean Distance mimo precoders
International Symposium on Information Theory, 2009Co-Authors: Fredrik Rusek, Dzevdan KapetanovicAbstract:In this work we study the problem of constructing precoders for spatially multiplexed multiple-input multiple output (MIMO) channels with close to optimal Minimum Euclidean Distance. In order to exploit the full potential of such designs, an ML detector must be used. Our design takes the decoding complexity into account and constrains it to a reasonable level. For our simplest case, the ML detector can be implemented by a Viterbi algorithm operating on a state space of size equal to the size of the modulation alphabet. The design problem will be relaxed by using precoders F such that F*H*HF is a cyclic Toeplitz matrix. Within this class of precoders, the optimal precoder can be found via linear programming. Of uttermost practical importance is the discovery that there only exist very few different effective channels HF even for large MIMO setups; thus, the optimization at the transmitter side reduces into choosing the best precoder from a small list. Receiver tests verify that our method improves upon the currently best precoder designs.
Ludovic Collin - One of the best experts on this subject based on the ideXlab platform.
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optimized max d min precoder assuming maximum squared Euclidean weight mapping and turbo detection
International Symposium on Turbo Codes and Iterative Information Processing, 2016Co-Authors: Nhat Quang Nhan, Ludovic Collin, Philippe Rostaing, Emanuel RadoiAbstract:The concatenation of multiple-input multiple-output (MIMO) linear precoder with an outer forward error correction (FEC) encoder is investigated at the transmitter. Turbo detection is applied at the receiver for the decoding. The bit-interleaved codeword is considered to be grouped and mapped directly onto the received constellation thanks to a MIMO symbol mapper. We exploit the optimal maximum squared Euclidean weight (MSEW) mappings for two forms of max-d min precoder to propose a novel precoder referred to as max-l min . The switching threshold between both forms is optimized by considering all received sequences whose binary mappings differ by exactly one bit and by first maximizing the Minimum Euclidean Distance within this set and then minimizing the number of pairs achieving it. Extrinsic information transfer (EXIT) chart is also used to validate the analysis. Simulation results show significant improvement, in terms of system error-rate performance, of the max-l min compared to the conventional max-d min .
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extension of the mimo precoder based on the Minimum Euclidean Distance a cross form matrix
IEEE Journal of Selected Topics in Signal Processing, 2008Co-Authors: Baptiste Vrigneau, Ludovic Collin, Philippe Rostaing, J Letessier, Gilles BurelAbstract:Under full channel state information at the transmitter side (Tx-CSI), MIMO precoders can be designed by the optimization of many pertinent criteria, like, for example, the maximizing post-processing signal-to-noise ratio (max-SNR or beamforming solution), or the minimizing weighted mean square error between transmit and receive vector-symbols (W-MMSE solution). These solutions decouple the MIMO channel into b parallel independent datastreams. This diagonal structure reduces the complexity of the maximum likelihood (ML) decisions but the diversity order of these schemes is limited. Recently, we proposed a precoder, max-dmjn solution, which optimizes the exact expression of the Minimum Euclidean Distance and leads to a non diagonal structure allowing to achieve maximum diversity order. However, the result is available only for two transmit datastreams (6 = 2) and BPSK and QPSK modulations. In this paper, we propose a heuristic method to deal with the case b > 2, which provides a suboptimal, but good solution to this general problem. The new precoder, Equal-dm;n (E-dmin), is based on a non diagonal cross-form structure. It significantly enhances the transmit diversity in the eigen-subchannels. We demonstrate that the achieved diversity order is greater than that of precoders with diagonal structure for the same number of datastreams despite a tradeoff between rate and diversity. This design can also ensure quality of service (QoS) by using an adapted power allocation strategy. Performance comparisons show the BER improvement for MIMO and MIMO-OFDM systems.
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optimal Minimum Distance based precoder for mimo spatial multiplexing systems
IEEE Transactions on Signal Processing, 2004Co-Authors: Ludovic Collin, Olivier Berder, P Rostaing, Gilles BurelAbstract:We describe a new precoder based on optimization of the Minimum Euclidean Distance d/sub min/ between signal points at the receiver side and for use in multiple-input multiple-output (MIMO) spatial multiplexing systems. Assuming that channel state information (CSI) can be made available at the transmitter, the three steps ( noise whitening, channel diagonalization and dimension reduction), which are currently used in investigations on MIMO systems, are performed. Thanks to this representation, an optimal d/sub min/ precoder is derived in the case of two different transmitted data streams. For quadrature phase-shift keying (QPSK) modulation, a numerical approach shows that the precoder design depends on the channel characteristics. Comparisons with maximum signal-to-noise ratio (SNR) strategy and other precoders based on criteria, such as water-filling (WF), Minimum mean square error (MMSE), and maximization of the Minimum singular value of the global channel matrix, are performed to illustrate the significant bit-error-rate (BER) improvement of the proposed precoder.