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Adaptive power allocation strategies for distributed space-time coding in cooperative MIMO networks

IET COMMUNICATIONS 2014年第7期8卷 1141-1150页

作者： Peng, Tong de Lamare, Rodrigo C. Schmeink, Anke Univ York Dept Elect Commun Res Grp York YO10 5DD N Yorkshire England Rhein Westfal TH Aachen Inst Theoret Informat Technol D-52056 Aachen Germany

Adaptive power allocation (PA) algorithms with different criteria for a cooperative multiple-input multiple-output network equipped with distributed space-time coding are proposed and evaluated. Joint constrained optimisation algorithms to determine the PA parameters and the receive filter are proposed for each transmitted symbol in each link, as well as the channel coefficients matrix. Linear receive filter and maximum-likelihood detection are considered with amplify-and-forward and decode-and-forward cooperation strategies. In these proposed algorithms, the elements in the PA matrices are optimised at the destination node and then transmitted back to the relay nodes via a feedback channel. The effects of the feedback errors are considered. Linear minimum mean square error expressions and the PA matrices depend on each other and are updated iteratively. Stochastic gradient algorithms are developed with reduced computational complexity. Simulation results show that the proposed algorithms obtain significant performance gains as compared with existing PA schemes.

关键词： channel allocation space-time codes cooperative communication MIMO communication channel coding filtering theory matrix algebra maximum likelihood detection amplify and forward communication decode and forward communication optimisation error statistics feedback stochastic processes gradient methods least mean squares methods adaptive power allocation strategy distributed space-time coding cooperative multiple input multiple output network joint constrained optimisation algorithm PA parameter determination symbol transmission channel coefflcients matrix linear receive filter maximum likelihood detection amplify and forward cooperation strategy decode and forward cooperation strategy destination node PA matrix optimisation relay nodes feedback channel feedback error linear minimum mean square error iterative method stochastic gradient algorithm computational complexity reduction

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Non-coherent distributed space-time coding techniques for two-way wireless relay networks

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SIGNAL PROCESSING 2013年第12期93卷 3371-3381页

作者： Alabed, Samer Pesavento, Marius Klein, Anja Tech Univ Darmstadt Commun Syst Grp D-64283 Darmstadt Germany Tech Univ Darmstadt Commun Engn Lab D-64283 Darmstadt Germany

To overcome the overhead involved with channel estimation, several non-coherent distributed space-time coding (DSTC) strategies for two-way wireless relay networks (TWRNs) using the amplify-and-forward and the decode-and-forward protocol have been recently proposed that do not require channel state information (CSI) at any node to decode the information symbols. In this paper, novel differential DSTC strategies for TWRNs using the two- and three-phase protocol are proposed. In our transmission schemes, the relays do not waste power to transmit information known at the respective destination nodes. This is achieved by combining the symbols from both terminals received at the relays into a single symbol of the unaltered constellation. Furthermore, in our strategies, the direct link between the communicating terminals can be naturally incorporated to further improve the diversity gain. Simulations show a substantially improved performance in terms of bit error rate (BER) of the proposed strategies as compared to the existing strategies. (C) 2012 Elsevier B.V. All rights reserved.

关键词： Two-way wireless relay networks distributed space-time coding Differential space-time coding Cooperative diversity

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Blind Cooperative Diversity Using distributed space-time coding in Block Fading Channels

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IEEE TRANSACTIONS ON COMMUNICATIONS 2010年第8期58卷 2447-2456页

作者： Tourki, Kamel Alouini, Mohamed-Slim Deneire, Luc Texas A&M Univ Qatar Elect & Comp Engn Program Doha Qatar King Abdullah Univ Sci & Technol Elect Engn Program Div Phys Sci & Engn Thuwal Mekkah Province Saudi Arabia Lab I3S CNRS UNSA F-06903 Sophia Antipolis France

Mobile users with single antennas can still take advantage of spatial diversity through cooperative space-time encoded transmission. In this paper, we consider a scheme in which a relay chooses to cooperate only if its source-relay channel is of an acceptable quality and we evaluate the usefulness of relaying when the source acts blindly and ignores the decision of the relays whether they may cooperate or not. In our study, we consider the regenerative relays in which the decisions to cooperate are based on a signal-to-noise ratio (SNR) threshold and consider the impact of the possible erroneously detected and transmitted data at the relays. We derive the end-to-end bit-error rate (BER) expression and its approximation for binary phase-shift keying modulation and look at two power allocation strategies between the source and the relays in order to minimize the end-to-end BER at the destination for high SNR. Some selected performance results show that computer simulations based results coincide well with our analytical results.

关键词： distributed space-time coding cooperative diversity blind cooperation regenerative relaying

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Differential distributed space-time coding With Imperfect Synchronization in Frequency-Selective Channels

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2015年第4期14卷 1811-1822页

作者： Avendi, M. R. Jafarkhani, Hamid Univ Calif Irvine Ctr Pervas Commun & Comp Irvine CA 92697 USA

Differential distributed space-time coding (D-DSTC) is a cooperative transmission technique that can improve diversity in wireless relay networks in the absence of channel information. Conventionally, it is assumed that channels are flat-fading and relays are perfectly synchronized at the symbol level. However, due to the delay spread in broadband systems and the distributed nature of relay networks, these assumptions may be violated. Hence, inter-symbol interference (ISI) may appear. This paper proposes a new differential encoding and decoding process for D-DSTC systems with multiple relays over slow frequency-selective fading channels with imperfect synchronization. The proposed method overcomes the ISI caused by frequency-selectivity and is robust against synchronization errors while not requiring any channel information at the relays and destination. Moreover, the maximum possible diversity with a decoding complexity similar to that of the conventional D-DSTC is attained. Simulation results are provided to show the performance of the proposed method in various scenarios.

关键词： distributed space-time coding differential encoding and decoding synchronization errors frequency-selective channels relay networks cooperative communications OFDM

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Adaptive Buffer-Aided distributed space-time coding for Cooperative Wireless Networks

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IEEE TRANSACTIONS ON COMMUNICATIONS 2016年第5期64卷 1888-1900页

作者： Peng, Tong de Lamare, Rodrigo C. CETUC PUC RIO Commun Res Grp BR-22451900 Rio De Janeiro Brazil

This work proposes adaptive buffer-aided distributed space-time coding schemes and algorithms with feedback for wireless networks equipped with buffer-aided relays. The proposed schemes employ a maximum likelihood receiver at the destination, and adjustable codes subject to a power constraint with an amplify-and-forward cooperative strategy at the relays. The adjustable codes are part of the proposed space-time coding schemes and the codes are sent back to relays after being updated at the destination via feedback channels. Each relay is equipped with a buffer and is capable of storing blocks of received symbols and forwarding the data to the destination if selected. Different antenna configurations and wireless channels, such as static block fading channels, are considered. The effects of using buffer-aided relays to improve the bit error rate (BER) performance are also studied. Adjustable relay selection and optimization algorithms that exploit the extra degrees of freedom of relays equipped with buffers are developed to improve the BER performance. We also analyze the pairwise error probability and diversity of the system when using the proposed schemes and algorithms in a cooperative network. Simulation results show that the proposed schemes and algorithms obtain performance gains over previously reported techniques.

关键词： Buffer-aided communications cooperative communications distributed space-time coding

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Differential distributed space-time coding with Imperfect Synchronization

Differential Distributed Space-Time Coding with Imperfect Sy...

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IEEE Global Communications Conference (GLOBECOM)

作者： Avendi, M. R. Poorkasmaei, Sina Jafarkhani, Hamid Univ Calif Irvine Ctr Pervas Commun & Comp Irvine CA 92697 USA

ISBN: (纸本)9781479935123

Differential distributed space-time coding (D-DSTC) has been considered to improve both diversity and data-rate in cooperative communications in the absence of channel information. However, conventionally, it is assumed that relays are perfectly synchronized in the symbol level. In practice, this assumption is easily violated due to the distributed nature of the relay networks. This paper proposes a new differential encoding and decoding process for D-DSTC systems with two relays. The proposed method is robust against synchronization errors and does not require any channel information at the destination. Moreover, the maximum possible diversity and symbol-by-symbol decoding are attained. Simulation results are provided to show the performance of the proposed method for various synchronization errors and the fact that our algorithm is not sensitive to synchronization error.

关键词： distributed space-time coding differential encoding and decoding synchronization error OFDM relay networks

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Successive Interference Cancellation for distributed space-time coding in Cooperative Cellular Systems

Successive Interference Cancellation for Distributed Space-T...

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7th International Conference on Wireless Communications, Networking and Mobile Computing (WiCOM)

作者： Liu, Luodan Wu, Zhuo Wang, Xin

ISBN: (纸本)9781424462520

A signal detection technique using successive interference cancellation (SIC) for uplink cooperative cellular systems is proposed in this paper, to suppress the interference caused by the cooperative transmission of two mobile users transmitting both their own information and the cooperative partner's information using distributed space-time coding (DSTC). Simulation results show that the proposed scheme outperforms the existing joint DSTC and equalization scheme in terms of system performance with time division multiple access.

关键词： distributed space-time coding cooperative communication successive interference cancellation cellular systems

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Relay Searching for distributed space-time coding in Decentralized Ad hoc Networks

Relay Searching for Distributed Space-Time Coding in Decentr...

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6th International ICST Conference on Communications and Networking in China (CHINACOM)

作者： Caitian, Qiyi Li, Yongzhao Gao, Xinbo Chen, Chen Xidian Univ Sch Elect Engn Xian 710071 Peoples R China Xidian Univ State Key Lab Integrated Serv Network Xian Peoples R China

ISBN: (纸本)9781457701016

space-time coding can effectively increase the communication capacity in multiple antenna systems. In case the terminals cannot be equipped with antenna arrays, distributed space-time coding (DSTC) can be applied to virtual MIMO channel which is constructed by several single-antenna terminals. A novel way of searching relays for DSTC based on decentralized ad hoc networks is proposed in this paper. The major merit of the new scheme is that the scope of selecting the cooperative relay node is far beyond the SISO transmission range. Thus more opportunities for cooperation are provided, even when the network density is low or the traffic is heavy. As a result, the transmission range is greatly extended without reducing the QoS. Besides, corresponding MAC and routing protocols are presented. Simulation results show that as compared with using SISO, end-to-end throughput of the network increases by 103.9%, while end-to-end latency is reduced by 87.6%.

关键词： distributed space-time coding cooperative relaying ad hoc networks cross-layer design

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Differential distributed space-time coding for Vehicle-to-Vehicle Networks 1

Differential Distributed Space-Time Coding for Vehicle-to-Ve...

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International Conference on Information and Communication Technology Research (ICTRC 2015)

作者： Al Maeeni, Sara Kapinas, Vasileios M. Muhaidat, Sami Karagiannidis, George K. Al-Araji, Saleh R. Khalifa Univ Elect & Comp Engn Dept Abu Dhabi U Arab Emirates Aristotle Univ Thessaloniki Dept Elect & Comp Engn Thessaloniki Greece

ISBN: (纸本)9781479989669

Differential distributed space-time coding ( DDSTC) has been proved to be suitable for wireless relay networks, since it can provide spatial diversity without the need for channel state information at neither the transmitter nor the receiver side. However, DDSTC suffers from significant error floor in fast-fading channel conditions with high Doppler frequencies due to rapid time variations. For this reason, multiple-symbol differential detection ( MSDD) has been proposed in the past, where the detection process involves a larger window size of the received symbols. So far, differential detection for vehicle-to-vehicle ( V2V) networks has been studied only for single Rayleigh channels. However, experimental and theoretical studies report that double Rayleigh can be considered as an appropriate fading channel model for V2V networks. In this paper, we assess the error performance of a DDSTC scheme operating in a V2V network using MSDD. Simulation results confirm that the error performance of such a system can be improved significantly with MSDD under different channel time-variation scenarios.

关键词： Differential detection distributed space-time coding double Rayleigh multiple-symbol differential detection time-varying channel vehicle-to-vehicle networks

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Diversity-multiplexing Tradeoff of Opportunistic Relaying Coded Cooperation and distributed space-time coding Coded Cooperation

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Procedia Computer Science 2017年 107卷 520-526页

作者： Xu Kun Li Xiao PLA Academy of National Defense Information Jiefang Garden Road No. 45 Wuhan 430010 China

In this paper, we analyze the diversity-multiplexing tradeoff (DMT) performance of opportunistic relaying coded cooperation (ORCC) and distributed space-time coding coded cooperation (DSTCCC) with arbitrary number of relays. Exact DMT curves are derived for two scenarios, i.e., when the source is included in cooperation (denoted by S1) or not (denoted by S2), by formulating the problem as linear optimization problem. The DMT curves of ORCC and DSTCCC are found to be identical for S1 (or S2), and S1 has better DMT performance than S2. Numerical results are provided to illustrate the analysis as well.

关键词： Diversity-multiplexing tradeoff opportunistic relaying distributed space-time coding coded cooperation.

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