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Cooperative space-time coding with Amplify-and- Forward Relaying

JOURNAL OF SIGNAL PROCESSING SYSTEMS FOR SIGNAL IMAGE AND VIDEO TECHNOLOGY 2012年第2期67卷 129-138页

作者： Al-nahari, Azzam Y. Dessouky, Moawad I. Abd El-Samie, Fathi E. Menoufia Univ Dept Elect & Elect Commun Fac Elect Engn Menoufia 32952 Egypt

Cooperative diversity using distributed space-time codes has been recently proposed to form virtual antennas in order to achieve diversity gain. In this paper, we consider a multi-relay network operating in amplify-and-forward (AAF) mode. Motivated by protocol III presented in (Nabar et al. 2004), we propose a cooperative diversity protocol implementing space-time coding for an arbitrary number of relay nodes when the source-destination link contributes in the second phase. We consider the use of real-orthogonal and quasi-orthogonal designs of space-time codes as they give better performance than random linear-dispersion codes. The pairwise error probability (PEP) has been derived and the theoretical analysis demonstrates that the proposed protocol achieves a diversity of order N + 1, where N is the number of relay nodes. No instantaneous channel state information is required at the relay nodes. The optimum power allocation that minimizes the PEP is obtained with numerical and theoretical analysis. The aggregate system power constraint is considered in the optimization. Simulation results demonstrate an improvement over the existing orthogonal protocols for different source-destination channel conditions. The results also show that the proposed scheme is robust to the channel estimation errors.

关键词： AAF relaying Cooperative communications space-time coding Spatial diversity

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SEMI-BLIND RECEIVER FOR TWO-HOP MIMO RELAYING SYSTEMS VIA SELECTIVE KRONECKER PRODUCT MODELING 8

SEMI-BLIND RECEIVER FOR TWO-HOP MIMO RELAYING SYSTEMS VIA SE...

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8th IEEE International Workshop on Computational Advances in Multi-Sensor Adaptive Processing (CAMSAP)

作者： Sokal, Bruno Haardt, Martin de Almeida, Andre L. F. Ilmenau Univ Technol Commun Res Lab Ilmenau Germany Fed Univ Ceara UFC Wireless Telecom Res Grp GTEL Fortaleza Ceara Brazil

ISBN: (纸本)9781728155494

In this paper we propose a new iterative semi-blind receiver for two-hop MIMO relaying systems using a tensor-based approach. We consider that both the source and the relay use a Khatri-Rao space time code for data transmission. We introduce a Selective Kronecker Product (SKP) modeling that allows to recast the received signal at the destination as a Tucker 3 model with a sparse core. The proposed SKP modeling eliminates the need of the source-destination (SD) link to initialize the receiver, as opposed to the receiver proposed in [1]. Our simulations show that our SKP-ALS receiver achieves a better performance than its state-of-the-art in the literature, that uses an additional SD link, with a lower computational complexity.

关键词： MIMO relaying systems space-time coding semi-blind receiver selective Kronecker product

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space-time Coded OTFS Modulation in High-Doppler Channels 89

Space-Time Coded OTFS Modulation in High-Doppler Channels

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89th IEEE Vehicular Technology Conference (VTC Spring)

作者： Augustine, Rose Mary Surabhi, G. D. Chockalingam, A. Indian Inst Sci Dept ECE Bangalore 560012 Karnataka India

ISBN: (纸本)9781728112176

Orthogonal time frequency space (OTFS) modulation is a 2-dimensional modulation technique designed in delay-Doppler domain, specially suited for doubly-dispersive fading channels. OTFS modulation uses additional transform operations at the transmitter and receiver on top of conventional multicarrier modulation operations, and is shown to achieve superior performance compared to OFDM in high-Doppler channels. It has been shown in the recent literature that the asymptotic diversity order of OTFS modulation is one. Also, OTFS with phase rotation using transcendental numbers has been shown to achieve full diversity in the delay-Doppler domain. In this paper, for the first time in the literature, we propose and investigate the use of space-time coding (STC) in OTFS modulation in a MIMO setting. We use the structure of Alamouti code, generalized to matrices, to achieve full transmit diversity in OTFS. We also show that the use of STC-OTFS along with phase rotation can achieve full diversity in both spatial and delay-Doppler domains. Also, STC-OTFS with phase rotation is found to achieve good diversity performance even with small frame sizes making it suited for low-latency applications.

关键词： OTFS modulation delay-Doppler domain space-time coding STC-OTFS full diversity

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Continuous Phase Modulation and space-time coding: A Candidate for Wireless Robotics

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WIRELESS PERSONAL COMMUNICATIONS 2012年第3期64卷 473-487页

作者： Deneire, Luc Lebrun, Jerome Lab I3S Sophia Antipolis France Univ Nice Sophia Antipolis CNRS F-06903 Sophia Antipolis France

The physical layer(s) of wireless robotics take advantage of current standards, like Bluetooth, Wifi, etc., each of them addressing a specific segment of wireless robotics. Wireless robotics has a wide range of needs, comprising low power, robustness and high data rate when video is used as well as the opportunity to use a large number of transceivers. To cover these needs and take benefit from these opportunities, we propose a new physical layer, based on continuous phase modulation (CPM) and space-time coding. CPM, already used in some standards like GSM and Bluetooth, enables the development of low power devices, but presents a low spectral efficiency. space-time coding on the other hand yields high spectral efficiency as well as enhanced robustness against the wireless channel. Moreover, space-time coding can take benefit of the large number of transceivers using cooperative communications. In this paper, after analysing the opportunities given by wireless robotics as well as its specific needs, we propose a new physical layer based on L-2-orthogonality for non-linear space-time codes. L-2-orthogonality of our codes is ensured by a bank of phase correction functions, maintaining phase continuity, but at the same time enabling low complexity decoding. We show that the code achieves full diversity and has full rate, for any number of transmit/receive antennas and any CPM parameter.

关键词： space-time coding Continuous phase modulation Physical layer

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space-time transmission scheme for asynchronous cooperative communications networks 7

Space-time transmission scheme for asynchronous cooperative ...

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7th IEEE Palestinian International Conference on Electrical and Computer Engineering (PICECE)

作者： El Astal, M. -T. Al Habbash, A. H. Abu-Hudrouss, A. M. P ICTRA CTRC Gaza Palestine IUG Dept Elect Engn Gaza Palestine

ISBN: (纸本)9781538662915

In this paper, an effective transmission scheme is proposed for asynchronous cooperative networks with two relays. The need for synchronization is obviated by allowing a single relay to be active in each time-slot of the transmission. However, the scheme still achieves a cooperative diversity order of two through some simple operations introduced at the relays while maintaining a single-symbol decoding complexity at the destination. Using the concept of spatial modulation, the scheme is extended for networks with an arbitrary number of relays to offer higher overall throughput as the number of relay increases. The numerical results demonstrate that the bit error rate (BER) performance of the proposed scheme, unlike that of the conventional scheme, does not degrade even when perfect synchronization is not guaranteed.

关键词： cooperative networks space-time coding imperfect synchronization full-diversity

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Constant-rate space-time Code Selection Design Using Particle Swarm Optimization 22

Constant-rate Space-Time Code Selection Design Using Particl...

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22nd Symposium on Image, Signal Processing and Artificial Vision (STSIVA)

作者： Mavares T, Dimas Oropeza, Miguel Velasquez, Reinaldo Pontificia Univ Javeriana Dept Elect & Ciencias Computac Secc Cali Cali Colombia ABB Stonefield Works Oulton Rd Stone ST15 0RS England Univ Carabobo Valencia Venezuela

ISBN: (纸本)9781728114910

In this paper, a constant-rate space-time code selection technique for multiple input-single output systems has been designed using the particle swarm optimization algorithm, finding channels threshold levels used by this technique. An analytical expression is proposed to be used as objective function, to address the problem of minimizing the bit-error rate. Results show that considerable energy-to-noise gains were obtained when using optimized threshold levels.

关键词： space-time coding transmit diversity MIMO particle swarm optimization PSO

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Effect of Mutual Coupling on the Performance of STCM-MIMO Systems

Effect of Mutual Coupling on the Performance of STCM-MIMO Sy...

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IEEE Wireless Communications and Networking Conference (WCNC)

作者： Azhiri, Fatemeh Asghari Abdolee, Reza Tazehkand, Behzad Mozaffari Univ Tabriz Dept Elect & Comp Engn Tabriz Iran Calif State Univ Dept Elect & Comp Engn Bakersfield CA USA

ISBN: (纸本)9781728109220

space-time coded massive (STCM) multiple-input multiple-output (MIMO) system provides superior bit error rate (BER) performance compared with the conventional space-time coding and massive MIMO techniques. The transmitter of the STCM-MIMO system consists of a large antenna array. In a practical system, the self-interference created by the signals transmitted by the elements of this antenna array, known as mutual coupling (MC), degrades the performance of the system. The MC effect is pronounced in communication systems with a large antenna array. On the other hand, increasing the number of transmitting antennas results in improved BER performance. Hence, there is a trade off in selecting the optimum number of transmitting antennas in an STCM-MIMO system. In order to take the impact of MC into account, we have derived an analytical expression for the received signal to accurately model the STCM-MIMO system under the existence of the MC effect. We present an algorithm to select the optimal number of antennas to minimize mutual coupling and the system bit error rate (BER). Through computer simulations, we investigate the BER performance of the STCM-MIMO system for different numbers of array elements.

关键词： massive MIMO 5G mutual coupling effect STCM-MIMO space-time coding

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Continuous Phase Modulation and space-time coding: A Candidate for Wireless Robotics

Continuous Phase Modulation and Space-Time Coding: A Candida...

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Strategic Workshop

作者： Deneire, Luc Lebrun, Jerome Lab I3S Sophia Antipolis France Univ Nice Sophia Antipolis CNRS F-06903 Sophia Antipolis France

关键词： space-time coding Continuous phase modulation Physical layer

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Closed-Form Channel Estimation for MIMO space-time Coded Systems Using a Fourth-Order Tensor-Based Receiver

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CIRCUITS SYSTEMS AND SIGNAL PROCESSING 2018年第3期37卷 1343-1357页

作者： de Araujo, Gilderlan T. de Almeida, Andre L. F. Univ Fed Ceara GTEL Wireless Telecom Res Grp Campus Pici S-NB 722 BR-60455760 Fortaleza Ceara Brazil

In this short paper, a new tensor-based receiver based on the fourth-order PARATUCK2 model combined with a structured PARAFAC model is formulated to solve the problem of channel estimation in a MIMO system. The proposed receiver is based on a modified space-time coding scheme that incorporates a formatting filter. Such a formatting filter is formed by a precoding matrix and a mapping matrix that load the coded signals to transmit antennas. The proposed receiver is divided into two steps. In the first step, closed-form channel estimation is performed by means of Kronecker and Khatri-Rao factorizations that rely on the singular value decomposition and the eigenvalue decomposition, respectively. In the second step, the transmitted symbols are linearly decoded from the estimated channel by exploiting the proposed space-time coding structure. Simulation results are presented to evaluate the performance of our tensor-based receiver in terms of NMSE and BER, demonstrating an improved performance compared to competing schemes.

关键词： space-time coding PARAFAC PARATUCK Channel estimation MIMO systems

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On MIMO Linear Physical-Layer Network coding: Full-Rate Full-Diversity Design and Optimization

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2018年第5期17卷 3498-3511页

作者： Shi, Long Yang, Tao Cai, Kui Chen, Pingping Guo, Tao Singapore Univ Technol & Design Sci & Math Cluster Singapore 487372 Singapore Univ Technol Sydney Sch Comp & Commun Ultimo NSW 2007 Australia Fuzhou Univ Coll Phys & Informat Fujian 361005 Peoples R China Chinese Univ Hong Kong Dept Informat Engn Hong Kong Hong Kong Peoples R China

This paper considers a multiuser communication network, where a receiver is set to compute functions of the messages from K users. All user nodes and the receiver are equipped with multi-antenna. We propose a space-time (ST) coded multiple-input multiple-output (MIMO) linear physical-layer network coding (LPNC) scheme that promises full-rate and full-diversity, while achieving the maximum coding gain of LPNC. In the proposed framework, the users' messages are encoded by the same linear dispersion ST code and transmitted simultaneously. The receiver exploits the MIMO LPNC mapping in reconstructing an arbitrary number of linearly network-coded (NC) messages. We derive the NC generator matrix that leads to the greatest coding gain and minimized error probability at the receiver. On top of that, we analytically show that the proposed ST coded LPNC scheme guarantees the full-diversity and full-rate transmission. The proposed method applies to a wide range of network configurations. Two case studies on: (1) MIMO two-way relay network and (2) MIMO multiple-access relay network are presented in this paper. For both case studies, numerical results are shown to demonstrate the performance improvement of the proposed scheme over conventional schemes by more than 4 dB, while the full-rate and full-diversity behaviors are in line with our analysis.

关键词： Physical-layer network coding space-time coding MIMO multiuser system compute-and-forward

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