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distributed space-time coding for multihop transmission in power line communication networks

IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS 2006年第7期24卷 1389-1400页

作者： Lampe, Lutz Schober, Robert Yiu, Simon Univ British Columbia Dept Elect & Comp Engn Vancouver BC V6T 1Z4 Canada

In, this paper, we consider transmission in relatively wide-stretched power line communication (PLC) networks, where repeaters are required to bridge the source-to-destination distance. In particular, it is assumed that each network node is a potential repeater and that multihop transmission is accomplished in an ad hoc fashion without the need for complex routing protocols. In such a scenario, due to the broadcasting nature of the power line channel, multiple repeater nodes may receive and retransmit the source message simultaneously. It is shown that, if no further signal processing is applied at the transmitter, simultaneous retransmission often deteriorates performance compared with single-node retransmission. We therefore advocate the application of distributed space-time block codes (DSTBCs) to the problem at hand. More specifically, we propose that each network node is assigned a unique signature sequence, which allows efficient combining at the receiver. Most notably, DSTBC-based retransmission does not require explicit collaboration among network nodes for multihop transmission and detection complexity is not increased compared with single-node retransmission. Numerical results for multihop transmission over PLC networks show that DSTBC-based retransmission achieves a considerably improved performance in terms of required transmit power and multihop delay compared with alternative retransmission strategies.

关键词： broadcast channel collision channel distributed space-time coding multihop transmission power line communication (PLC) repeater

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distributed space-time coding scheme with differential detection and power allocation for cooperative relay network

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TELECOMMUNICATION SYSTEMS 2017年第3期66卷 431-445页

作者： Xu, Weiye Wang, Qingyun Lin, Min Nanjing Inst Technol Sch Commun Engn Nanjing Jiangsu Peoples R China PLA Univ Sci & Technol Coll Commun Engn Nanjing Jiangsu Peoples R China

By introducing orthogonal space-time coding (STC) scheme in wireless cooperative relay network, two distributed differential STC (DSTC) schemes based on the amplify-and-forward (AF) and decode-and-forward (DF) methods are, respectively, developed. The scheme performance is investigated in symmetric and asymmetric wireless relay networks. The presented schemes require no channel information at both relay terminals and destination terminal, and have linear decoding complexity when compared with the existing scheme. Moreover, they are suitable for the application of different constellation modulations and DSTC schemes, and thus provide more freedoms of design. Besides, the power allocations between source and relay terminals are jointly optimized to minimize the system pairwise error probability for symmetric and asymmetric networks, and two practical methods are presented to solve the complicated optimized problem from asymmetric network. Simulation results show that the scheme with DF method has better performance than that with AF method due to no amplification of noise power, but the performance superiority will decrease at high SNR due to the error propagation of decoding at the relays. Furthermore, the distributed DSTC schemes with optimal power allocation have better performance than those with conventional fixed power allocation.

关键词： distributed space-time coding Differential detection Power allocation Amplify-and-forward Decode-and-forward Asymmetric relay network

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distributed space-time coding for Full-Duplex Asynchronous Cooperative Communications

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2012年第7期11卷 2680-2688页

作者： Liu, Yi Xia, Xiang-Gen Zhang, Hailin Xidian Univ State Key Lab Integrated Serv Network Xian 710071 Peoples R China Univ Delaware Dept Elect & Comp Engn Newark DE 19716 USA Chonbuk Natl Univ Jeonju South Korea

In this paper, we propose two distributed linear convolutional space-time coding (DLC-STC) schemes for full-duplex (FD) asynchronous cooperative communications. The DLC-STC Scheme 1 is for the case of the complete loop channel cancellation, which achieves the full asynchronous cooperative diversity. The DLC-STC Scheme 2 is for the case of the partial loop channel cancellation and amplifying, where some loop signals are used as the self-coding instead of treated as interference to be directly cancelled. We show this scheme can achieve full asynchronous cooperative diversity. We then evaluate the performance of the two schemes when loop channel information is not accurate and present an amplifying factor control method for the DLC-STC Scheme 2 to improve its performance with inaccurate loop channel information. Simulation results show that the DLC-STC Scheme 1 outperforms the DLC-STC Scheme 2 and the delay diversity scheme if perfect or high quality loop channel information is available at the relay, while the DLC-STC Scheme 2 achieves better performance if the loop channel information is imperfect.

关键词： Asynchronous cooperative diversity cooperative communications distributed space-time coding full-duplex transmission

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distributed space-time coding with decode-andforward-amplify-and-forward selection relaying protocol in cooperative wireless sensor networks

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IET WIRELESS SENSOR SYSTEMS 2013年第1期3卷 9-15页

作者： Zhang, Tian Shandong Univ Sch Informat Sci & Engn Jinan 250100 Peoples R China Tsinghua Univ Natl Lab Informat Sci & Technol TNList State Key Lab Microwave & Digital Commun Dept Elect Engn Beijing 100084 Peoples R China

distributed space-time coding (DSTC) with an efficient relaying protocol, referred to as amplify-and-forward and decode-and-forward (DF-AF) selection relaying, has not received much attention yet. In the DF-AF selection relaying-aided DSTC transmissions, each relay could adaptively process the received signal according to its decoding state to improve the performance. In this study, the authors analyse the pairwise error probability (PEP) performance, the diversity order and the union bound on the error probability of the DSTC with DF-AF selection relaying in cooperative wireless sensor networks. More specifically, by introducing a random variable vector to denote the decoding state of the relays, the upper bounds of PEP are derived first for the DSTC with DF-AF selection relaying based on the Chernoff bound. Then, the diversity order and the union bound on the error probability are obtained based on the upper bounds of PEP. Finally, simulation results verify the theoretical analysis and demonstrate that the DSTC with DF-AF selection relaying has better error performance than the DSTC with DF protocol and the DSTC based on AF protocol.

关键词： error statistics protocols space-time codes wireless sensor networks amplify and forward communication cooperative communication decode and forward communication distributed space-time coding decode-and-forward–amplify-and-forward selection relaying protocol cooperative wireless sensor networks pairwise error probability diversity order Chernoff bound

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distributed space-time coding and equalization for cooperative cellular communication system

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IEEE TRANSACTIONS ON CONSUMER ELECTRONICS 2008年第1期54卷 47-51页

作者： Xu, Jian Choi, JinYong Seo, Jong-Soo Yonsei Univ Dept Elect & Elect Engn Seoul 120749 South Korea

Multiple antenna techniques are hard to implement because the physical size of the mobile phones or the hardware capability is limited. In this paper, a joint distributed space time coding and equalization technique is proposed for cellular communication system in order to obtain the advantages of MIMO system requiring only one antenna for each mobile user. The proposed scheme can reduce two time slots during the cooperation phase. Simulation results show that the proposed scheme outperforms the conventional distributed space-time coded cooperative scheme in terms of system capacity. And also it achieves the same diversity gain as the conventional distributed space-time coded cooperative scheme with time division multiple access.(1).

关键词： distributed space-time coding cooperative communication Alamouti structure equalization

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distributed space-time coding for Two-Path Successive Relaying

Distributed Space-Time Coding for Two-Path Successive Relayi...

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IEEE Global Telecommunications Conference (GLOBECOM 2010)

作者： Tian, Feng Zhang, Wei Ma, Wing-Kin Ching, P. C. Chinese Univ Hong Kong Dept Elect Engn Hong Kong Hong Kong Peoples R China Univ New South Wales Sch Elect Engn & Telecommun Sydney NSW Australia

ISBN: (纸本)9781424456383

A distributed space-time block code (STBC) based on a decode-and-forward (DF) protocol is proposed for two-path successive relaying. By making the two relay nodes transmit and listen in turn, the proposed distributed STBC can achieve not only full rate but also full diversity when the relay nodes can correctly decode the information symbols from the source node and when the inter-relay channels are sufficiently strong. We also analyze the situation when there are decoding errors at the relay nodes. We notice in this case full diversity will not be achieved. We then propose the application of selection relaying to the proposed distributed STBC to ensure that full rate and full diversity can still be obtained with decoding errors at the relay nodes.

关键词： decode and forward communication decode-and-forward protocol decoding errors distributed space-time block code distributed space-time coding inter-relay channels protocols relay nodes space-time block codes two-path successive relaying

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Impact of CSI on distributed space-time coding in Wireless Relay Networks

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2009年第5期8卷 2580-2591页

作者： Kobayashi, Mari Mestre, Xavier SUPELEC Gif Sur Yvette France CTTC Barcelona Spain

We consider a two-hop wireless network where a transmitter communicates with a receiver via All relays with an amplify-and-forward (AF) protocol. Recent works have shown that the sophisticated linear processing such as beamforming and distributed space-time coding (DSTC) at relays enables to improve the AF performance. However, the relative utility of these strategies depends on the available channel state information at transmitter (CSIT), which in turn depends on the system parameters such as the speed of the underlying fading channel and that of training and feedback procedures. Moreover, it is of practical interest to have a single transmit scheme that handles different CSIT scenarios. This motivates us to consider a unified approach based on DSTC that potentially provides diversity gain with statistical CSIT and exploits some additional side information if available. Under individual power constraints at the relays, we optimize the amplifier power allocation such that pairwise error probability conditioned on the available CSIT is minimized. Under perfect CSIT, we propose an on-off gradient algorithm that efficiently finds a set of relays to switch on. Under partial and statistical CSIT, we propose a simple waterfilling algorithm that yields a non-trivial solution between maximum power allocation and a generalized STC that equalizes the averaged amplified noise for all relays. Moreover, we derive the closed-form solutions for M = 2 and in certain asymptotic regimes that enable an easy interpretation of the proposed algorithms. It is found that an appropriate amplifier power allocation is mandatory for DSTC to offer sufficient diversity and power gain in a general network topology.

关键词： Cooperative communications relay channel pairwise error probability channel state information distributed space-time coding

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Optimal SNR-based selection relaying scheme in multi-relay cooperative networks with distributed space-time coding

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IET COMMUNICATIONS 2010年第6期4卷 619-630页

作者： Bastami, A. H. Olfat, A. Univ Tehran Signal Proc & Commun Syst Lab Sch Elect & Comp Engn Tehran 14174 Iran

Error propagation from the relay to the destination is a major drawback of digital relaying protocols that substantially diminishes the cooperative diversity gain of the system. Appropriately designed selection relaying schemes can effectively mitigate this phenomenon and improve the diversity order, especially when the source-relay channel state information (CSI) is not available at the destination. In this study, the authors investigate the SNR-based selection relaying scheme in a multi-relay cooperative network that employs the distributed space-time coding (DSTC) strategy. The authors present a closed-form expression for the end-to-end bit error probability (BEP) of the system. It is demonstrated that the orthogonality of the space-time coded signals transmitted by the relays is not preserved under the error propagation from the relays to the destination and this gives rise to intersymbol interference at the destination. The SNR loss and intersymbol interference caused by the error propagation substantially diminish the diversity order of the system. The error propagation can be effectively mitigated by employing appropriate thresholds at the relays. The authors derive a closed-form expression for the optimal threshold that minimises the end-to-end BEP of the system. The authors also analyse the asymptotic behaviour of the BEP and demonstrate that by employing the optimal threshold the full diversity order is achieved. Furthermore, the authors propose a class of thresholds that are independent of the network geometry and also provide full diversity order. By employing these thresholds, each relay node can decide to forward or remain silent independent of other relay nodes.

关键词： intersymbol interference SNR based selection relaying scheme distributed space-time coding closed-form expression channel state information end-to-end bit error probability multi-relay cooperative networks digital relaying protocols error propagation error statistics space-time codes Codes

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Combination of MRC and distributed space-time coding in Networks with Multiple-Antenna Relays

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2010年第8期9卷 2550-2559页

作者： Jing, Yindi Univ Alberta Dept Elect & Comp Engn Edmonton AB T6G 2M7 Canada

distributed space-time coding (DSTC) is a cooperative scheme for wireless relay networks that achieves full diversity without channel information at the relays. In this paper, the use of maximum-ratio combining (MRC) at multiple-antenna relays in combination with DSTC is proposed. Simulation and theoretical analysis show that the new scheme outperforms the original DSTC. In some network scenarios, it can even improve the scaling of the error rate with the transmit power. Furthermore, the proposed scheme requires a shorter training interval than DSTC.

关键词： Cooperative network distributed space-time coding maximum-ratio combining diversity gain pairwise-error probability

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Co-ordinate Interleaved distributed space-time coding for Two-Antenna-Relays Networks

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2009年第4期8卷 1783-1791页

作者： Harshan, J. Rajan, B. Sundar Indian Inst Sci Dept Elect Commun Engn Bangalore 560012 Karnataka India

distributed space time coding for wireless relay networks when the source, the destination and the relays have multiple antennas have been studied by Jing and Hassibi. In this set-up, the transmit and the receive signals at different antennas of the same relay are processed and designed independently, even though the antennas are colocated. In this paper, a wireless relay network with single antenna at the source and the destination and two antennas at each of the R relays is considered. A new class of distributed space time block codes called Co-ordinate Interleaved distributed space-time Codes (CIDSTC) are introduced where, in the first phase, the source transmits a T-length complex vector to all the relays;and in the second phase, at each relay, the in-phase and quadrature component vectors of the received complex vectors at the two antennas are interleaved and processed before forwarding them to the destination. Compared to the scheme proposed by Jing-Hassibi, for T >= 4R, while providing the same asymptotic diversity order of 2R, CIDSTC scheme is shown to provide asymptotic coding gain with the cost of negligible increase in the processing complexity at the relays. However, for moderate and large values of P, CIDSTC scheme is shown to provide more diversity than that of the scheme proposed by Jing-Hassibi. CIDSTCs are shown to be fully diverse provided the information symbols take value from an appropriate multidimensional signal set.

关键词： Cooperative communication distributed space-time coding co-ordinate interleaving coding gain

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