naa a22 4500 510792235 CHVBK 20180411083323.0 cr unu---uuuuu 180411e20130801xx s 000 0 eng 10.1007/s11277-012-0975-x doi (NATIONALLICENCE)springer-10.1007/s11277-012-0975-x A Cyclic Shift Relaying Scheme for Asynchronous Two-way Relay Networks [Elektronische Daten] [Zhaoxi Fang, Feng Liang, Shaozhong Zhang, Tao Peng] Perfect time synchronization among multiple relay nodes is quite difficult to realize in distributed relay networks. In this paper, we proposed a cyclic prefix (CP) assisted cyclic shift relaying (CFR) scheme for asynchronous two-way amplify-and-forward (AF) relay networks over flat fading channels. In the proposed scheme, a CP is inserted at the two source nodes to combat the asynchronous delays. Each relay amplifies the received mixed asynchronous signals after CP removal, and a cyclic delay is introduced to further improve the system performance. With the CP and the cyclic delay, the multiple flat fading relay channels are transformed into a multipath fading channel. As a result, low complexity frequency domain equalizers, such as zero-forcing and minimum mean square error (MMSE) equalizer, can be used to recover the transmit signal. Furthermore, the performance of the proposed CFR scheme with MMSE equalizer is analyzed and closed-form expression for the lower bound of uncoded bit error rate (BER) performance is derived. Based upon this lower bound, we also investigate the power allocation among the sources and the relays to improve the system performance. Finally, extensive numerical results are provided to show the BER and frame error rate performance of the proposed CFR scheme. Springer Science+Business Media New York, 2012 Asynchronous two-way relay nationallicence Cyclic shift relaying nationallicence Amplify-and-forward nationallicence Frequency domain equalization nationallicence Fang Zhaoxi School of Electronic and Information Engineering, Zhejiang Wanli University, 315100, Ningbo, Zhejiang, China aut Liang Feng School of Electronic and Information Engineering, Zhejiang Wanli University, 315100, Ningbo, Zhejiang, China aut Zhang Shaozhong School of Electronic and Information Engineering, Zhejiang Wanli University, 315100, Ningbo, Zhejiang, China aut Peng Tao School of Electronic and Information Engineering, Zhejiang Wanli University, 315100, Ningbo, Zhejiang, China aut Wireless Personal Communications Springer US; http://www.springer-ny.com 71/4(2013-08-01), 2863-2876 0929-6212 71:4<2863 2013 71 11277 https://doi.org/10.1007/s11277-012-0975-x text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s11277-012-0975-x text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Fang Zhaoxi School of Electronic and Information Engineering, Zhejiang Wanli University, 315100, Ningbo, Zhejiang, China aut NATIONALLICENCE 700 1- Liang Feng School of Electronic and Information Engineering, Zhejiang Wanli University, 315100, Ningbo, Zhejiang, China aut NATIONALLICENCE 700 1- Zhang Shaozhong School of Electronic and Information Engineering, Zhejiang Wanli University, 315100, Ningbo, Zhejiang, China aut NATIONALLICENCE 700 1- Peng Tao School of Electronic and Information Engineering, Zhejiang Wanli University, 315100, Ningbo, Zhejiang, China aut NATIONALLICENCE 773 0- Wireless Personal Communications Springer US; http://www.springer-ny.com 71/4(2013-08-01), 2863-2876 0929-6212 71:4<2863 2013 71 11277 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer