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Noncoherent OSTBC-OFDM for MIMO and Cooperative Communications: Perfect Channel Identifiability and Achievable Diversity Order

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IEEE TRANSACTIONS ON SIGNAL PROCESSING 2012年第9期60卷 4849-4863页

作者： Chang, Tsung-Hui Ma, Wing-Kin Huang, Chuan-Yuan Chi, Chong-Yung Natl Tsing Hua Univ Dept Elect Engn Hsinchu 30013 Taiwan Natl Tsing Hua Univ Inst Commun Engn Hsinchu 30013 Taiwan Chinese Univ Hong Kong Dept Elect Engn Shatin Hong Kong Peoples R China Ind Technol Res Inst Hsinchu 31040 Taiwan

This paper considers the context of orthogonal space-time block coded OFDM (OSTBC-OFDM) without channel state information at the receiver. Assuming noncoherent maximum-likelihood detection, the interest herein lies in detection within one OSTBC-OFDM block, motivated by its capability of accommodating relatively fast block fading channels. Our investigation focuses on analysis aspects, where we seek to establish practical noncoherent BPSK/QPSK OSTBC-OFDM schemes that have provably good channel identifiability and diversity properties. We consider perfect channel identifiability (PCI), a strong condition guaranteeing unique noncoherent channel identification for any (nonzero) channel. Through a judicious design involving special OSTBCs and pilot placement, we propose an OSTBC-OFDM scheme that is PCI-achieving and consumes fewer pilots compared to conventional pilot-aided channel estimation methods. We further our analysis by showing that a PCI-achieving scheme also achieves maximal noncoherent spatial diversity for the Kronecker Gaussian spatial-temporal channel fading model, which covers the popular i.i.d. Rayleigh fading channel and a variety of correlated and sparse multipath channels. All these results are developed in parallel for the centralized point-to-point MIMO scenario and a distributed relay communication scenario. For the latter scenario, our diversity analysis shows that the PCI-achieving scheme can also achieve maximal noncoherent cooperative diversity. The performance merits of the proposed PCI-achieving scheme are demonstrated by simulations.

关键词： distributed space-time coding diversity maximum-likelihood detection noncoherent detection OSTBC-OFDM unique channel identifiability

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Limited-shift-full-rank matrices with applications in asynchronous cooperative communications

Limited-shift-full-rank matrices with applications in asynch...

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IEEE Global Telecommunications Conference (GLOBECOM 07)

作者： Shang, Yue Xia, Xiang-Gen Univ Delaware Dept Elect & Comp Engn Newark DE 19716 USA

ISBN: (纸本)1424410436

Shift-full-rank (SFR) matrices are matrices that have full row rank no matter how their rows are shifted. SFR matrices have been used lately as generator matrices for a family of space-time trellis codes to achieve full diversity in asynchronous cooperative communications, where the numbers of columns of the SFR matrices correspond to the memory sizes of the trellis codes. A systematic construction of SFR matrices, including the shortest (square) FR (SSFR) matrices, has been also previously proposed. In this paper, we study a variation of SFR matrices with a relaxed condition: limited-shift-full-rank (LT-SFR) matrices, i.e., the matrices that have full row rank no matter how their rows are shifted as long as the shifts are within some range called delay tolerance. As the generator matrices for the previously proposed space-time trellis codes, LT-SFR matrices can guarantee asynchronous full diversity of the corresponding codes when the timing errors are within the delay tolerance. Therefore, due to the relaxed condition imposed on LT-SFR matrices, more eligible generator matrices than SFR matrices become available.

关键词： asynchronous cooperative communications cooperative diversity distributed space-time coding limited-shift-full-rank (LT-SFR) matrices relay networks shift-full-rank (SFR) matrices

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space-time coding design for multiple source nodes full-duplex cooperative communication 95

Space-time coding design for multiple source nodes full-dupl...

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IEEE 95th Vehicular Technology Conference: (VTC-Spring)

作者： Liu, Ligang Qu, Qing Zhou, Bin Zhao, Yu Bu, Zhiyong Chinese Acad Sci Shanghai Inst Microsyst & Informat Technol Shanghai 200050 Peoples R China Univ Chinese Acad Sci Beijing 100049 Peoples R China

ISBN: (数字)9781665482431

ISBN: (纸本)9781665482431

Cooperative communication is a promising technology to improve the performance of resource-limited or cost-sensitive single antenna wireless equipment. Moreover, full duplex (FD) could theoretically double the spectral efficiency of a cooperative communication system comparing to the conventional half duplex (HD) communication. Although researchers have studied FD cooperative communication with two source nodes, and proposed an Alamouti-style space-time code, there is not much works on multiple source nodes scenarios yet. This article presents our results on the FD cooperative communication with multiple source nodes. We provide two orthogonal space-time block codes (OSTBC) for both three and four source nodes scenarios. The proposed codes skillfully share data in as less time slots as possible by taking advantages of the FD communication. Consequently, spectral efficiency of the FD cooperation is improved. Furthermore, the proposed codes provide full diversity in addition to a simple ML decoding. Finally, computer simulations verify the performance of the proposed OSTBC design.

关键词： cooperative communication virtual MIMO full duplex space-time coding distributed space-time coding

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Interference Cancellation in distributed space-time Coded Wireless Relay Networks

Interference Cancellation in Distributed Space-Time Coded Wi...

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IEEE International Conference on Communications (ICC 2009)

作者： Jing, Yindi Jafarkhani, Hamid Univ Alberta Edmonton AB T6G 2M7 Canada Univ Calif Irvine Irvine CA 92717 USA

ISBN: (纸本)9781424434343

This paper considers the interference cancellation (IC) problem in multi-user wireless relay networks. First, it is shown that using distributed space-time coding (DSTC), the multiple antenna IC scheme previously proposed for systems with direct transmissions can be applied to relay networks. The ML decoding after full IC can be performed symbol by symbol. Then, by allowing IC at relays, a new degree of freedom in relay network design is discovered. With this new idea, the required number of antennas at the receiver for full IC can be reduced and a balance between diversity and delay can be obtained.

关键词： Wireless relay networks distributed space-time coding interference cancellation orthogonal and quasi-orthogonal codes

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A Cooperative Protocol for Spectral-Efficient Cognitive Relay Networks

A Cooperative Protocol for Spectral-Efficient Cognitive Rela...

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IEEE Global Conference on Signal and Information Processing (GlobalSIP)

作者： Argyriou, Antonios Univ Thessaly Dept Elect & Comp Engn Filellinon Volos Greece

ISBN: (纸本)9781479970889

In this paper we propose a cooperative protocol for cognitive wireless networks that can improve the overall system spectral efficiency when a secondary user (SU) incorrectly transmits over the same resource with the primary user (PU). The interfering transmissions are received at relay nodes, that form the cooperative network, and are decoded with successive interference cancellation (SIC). Depending on the decoding results, each relay applies independently a space-time code (STC) to the result and then the relays forward the coded signals simultaneously. The advantages of the protocol are first that it operates passively without the need for source cooperation, and second that it does not adopt a different mode of cooperation for different average channel conditions. Comparative simulations with a state-of-the-art multi-source transmission protocol reveal that our protocol can minimize the impact of incorrectly detecting a PU transmission from the perspective of the overall system spectral efficiency.

关键词： Cognitive network cooperative protocol successive interference cancellation Alamouti code space-time block coding distributed space-time coding wireless networks

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Channel Training and Coherent Decodings in Amplify-and-Forward Relay Network

Channel Training and Coherent Decodings in Amplify-and-Forwa...

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54th Annual IEEE Global Telecommunications Conference (GLOBECOM)

作者： Sun, Sun Jing, Yindi Univ Alberta Edmonton AB Canada

ISBN: (纸本)9781424492688

In this paper, channel training and coherent decodings with channel estimation errors are investigated in a relay network with one single-antenna transmitter, two single-antenna relays, and one double-antenna receiver. A two-stage training scheme is proposed to estimate both the relay-receiver and transmitter-relay channels at the receiver. We use distributed space-time coding (DSTC) for data transmission and investigate the effect of channel estimation errors on the diversity. Two coherent decodings are considered: mismatched decoding in which the channel estimations are treated as if perfect, and matched decoding which takes into account the estimation errors. We show that for full diversity, mismatched decoding requires at least 6 symbol intervals for training, while 4 symbol intervals for training are enough for matched decoding. On the other hand, the complexity of matched decoding is much higher. To achieve a balance between performance and complexity, an adaptive decoding scheme is proposed. Simulated network error rates are shown to justify the analytical results.

关键词： Channel estimation Complexity theory Decoding Estimation error Receivers Relays Training amplify and forward communication amplify and forward relay network channel coding channel estimation channel estimation errors channel training coherent decoding data transmission decoding distributed space-time coding double-antenna receiver mismatched decoding relay-receiver single-antenna relays single-antenna transmitter transmitter-relay channel two-stage training scheme

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A Stackelberg Game for DSTC-Based Cognitive Radio Networks with Multiple Cooperative Relays 8

A Stackelberg Game for DSTC-Based Cognitive Radio Networks w...

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8th International Conference on Intelligent Networking and Collaborative Systems (INCoS)

作者： Wang, Lijie Yuan, Bo Zhu, Dangfeng Tang, Yi Xian Satellite Control Ctr Xian Peoples R China Natl Key Lab Sci & Technol Informat Syst Secur Beijing Peoples R China

ISBN: (纸本)9781509041237

The spectrum utility can be improved when cooperative communication technology is incorporated into cognitive radio network, and both the licensed users and secondary users can benefit from cooperating. In this cooperative cognitive radio network, a primary user and multiple secondary users cooperate with each other adopting space-time coding relay scheme to benefit win-win cooperation. Considering the primary user owns the spectrum and both the primary user and secondary users are selfish and reasonable, this cooperative cognitive network is formulated as a Stackelberg game. Based on utility maximizing, this paper studies the spectrum allocation and relay selection problem. A spectrum allocation algorithm is derived under given number of secondary users, and a low complexity relay selection strategy is proposed to maximize the utility of the primary user while guaranteeing the data rate of the primary user and the fairness among the secondary users. Numerical results show the feasibility and validity of the proposed relay selection scheme.

关键词： Cooperative cognitive radio network distributed space-time coding Spectrum utility Spectrum allocation Relay selection

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Cooperative Broadcast Channels with Hybrid ARQ

Cooperative Broadcast Channels with Hybrid ARQ

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22nd IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC)

作者： Narasimhan, Ravi Appl Micro Circuits Corp Sunnyvale CA 94089 USA

ISBN: (纸本)9781457713484

The throughput performance is studied for a two-user wireless broadcast channel with hybrid automatic repeat request (HARQ) and user cooperation. Two transmission schemes are considered: superposition coding (SC) and frequency-division multiplexing (FDM). During the initial HARQ rounds, the access point (AP) transmits messages to the users using either SC or FDM. If a user is successful, the AP uses all resources to transmit to the other user in subsequent HARQ rounds. Meanwhile, the successful user attempts to decode the other user's message and cooperate simultaneously with the AP, as long as the maximum number of HARQ rounds L has not been reached. The cooperative transmissions use distributed space-time coding to avoid the half-duplex penalty. HARQ transmissions continue until success for both users or until L HARQ rounds have elapsed. Cooperation provides throughput gains subject to quality-of-service (QoS) constraints, even when the path loss between users is greater than that between each user and the AP.

关键词： Bandwidth Delta modulation Frequency division multiplexing HARQ Mutual information Signal to noise ratio Throughput Upper bound automatic repeat request broadcast channels channel coding cooperative broadcast channel cooperative communication distributed space-time coding frequency division multiplexing frequency-division multiplexing half-duplex penalty hybrid ARQ hybrid automatic repeat request quality of service quality of service space-time codes superposition coding throughput performance user cooperation wireless broadcast channel wireless channels

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Interference Decoding in Cellular Wireless Relay Networks with space-time coding

Interference Decoding in Cellular Wireless Relay Networks wi...

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IEEE Wireless Communications and Networking Conference (WCNC)

作者： Argyriou, Antonios Univ Thessaly Dept Elect & Comp Engn Volos Greece

ISBN: (纸本)9781479930838

In this paper we propose a cooperative protocol and a symbol decoding algorithm that target improved performance in the presence of inter-cell interference (ICI) in wireless cellular networks. Our scheme uses the wireless signals that interfere at relay nodes located at the cell edge instead of discarding them. The relays are non-regenerative and apply a space-time code (STC) to the interfered signal. Subsequently, the relays broadcast the coded signals. At the destinations the interfered and ST-coded signals are decoded in two stages. First by decoding the STC, and then by applying successive interference cancellation (SIC). Simulation results for Rayleigh fading channel reveal significant throughput benefits even in the low SNR regime. We also present results for a small-scale LTE-based cellular scenario and we compare our scheme against the Coordinated MultiPoint (CoMP) transmission mode of LTE-A that is based on beamforming.

关键词： Interference decoding cooperative protocol Alamouti code space-time block coding distributed space-time coding physical layer network coding wireless networks ICI LTE-A

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Coded Cooperative Networks with Channel Estimation Technique

Coded Cooperative Networks with Channel Estimation Technique

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5th IEEE Asia-Pacific Conference on Applied Electromagnetics (APACE)

作者： Elfituri, Mohamed Gheryani, Mabruk Collage Elect & Elect Technol Dept Commun Engn Benghazi Libya Univ Concordia Dept Elect & Comp Engn Montreal PQ Canada

ISBN: (纸本)9781467331166

This paper proposes a coherent distributed convolutional-based coding scheme with channel estimation based on pilot signals. Instead of transmitting the second frames on orthogonal sub-channels from the source and relay nodes to the destination, we used Alamouti scheme in the second frame. In particular, we assume that the channel state information is estimated at all nodes involved in the transmission process. Assuming decode-and-forward (DF) relaying, we derived upper bounds on the bit error rate (BER) for M-ary phase shift keying (M-PSK) transmission with channel estimation errors. Our analytical results have shown that a performance close to perfect channel knowledge can be obtained when the number of pilot symbols increases. At low pilot to noise ratio (PNR), the proposed scheme cannot provide significant performance improvements. Finally, the performance of the system degrades significantly. This diversity degradation si attributed to the channel estimation errors made at the relay and destination nodes.

关键词： distributed space-time coding channel estimation relay channels pilot-to-noise

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