An Improved STBC Structure and Transmission Scheme for High Rate and Reliability in OFDMA Cooperative Communication

Space-time block code(STBC) has been studied to get full diversity and full rate in multiple input multiple output(MIMO) system. Achieving full rate is difficult in cooperative communications due to the each user consumes the time slots for transmitting information in cooperation phase. So combining MIMO systems with cooperative communications has been researched for full diversity and full rate. In orthogonal frequency division multiple access (OFDMA) system, it is an alternative way that each user shares their allocated subchannels instead of using the MIMO system to improve the transmission rate. In this paper, a Decode-and-forward (DF) based cooperative communication scheme is proposed. The proposed scheme has improved transmission rate and reliability in multi-path fading channel of the OFDMA up-link condition by modified STBC structure and subchannel sharing.

Authors:

• Hyoung-Muk Lim
• Won-Jun Choi
• Jae-Seon Yoon
• Hyoung-Kyu Song

Keywords:

• cooperation
• improved rate
• OFDMA
• STBC.

References:

[1] S.M. Alamouti, "A Simple Transmit Diversity Technique for Wireless
Communications," IEEE J. Select. Areas Commun.,vol. 16, no. 8, pp.
1451- 1458, Oct. 1998.
[2] Y. Akyildiz and B. D. Rao, Maximum ratio combining performance with
imperfect channel estimates, IEEE International Conference,vol. 3, pp.
2485-2488. May 2002.
[3] A. Sendonaris, E. Erkip, and B. Aazhang, User Cooperation Diversity
Part I and Part II, IEEE Trans. Commun., vol. 51, no. 11, pp. 1927-
1948, Nov. 2003.
[4] J. Niu, and I.-T. Lu, "Coded Cooperation in OFDMA Systems," Information
Sciences and Systems 2006 40th Annual Conference on, pp. 300
- 305, Mar. 2006.
[5] So-Young Yeo, Jae-Seon Yoon, Myung-Sun Baek, Young-Hwan You, and
Hyoung-Kyu Song, Efficient Techniques in OFDM System with Channel
Evaluation, IEICE Trans. on Commun., vol. E89-B, no. 10, pp. 2945-
2948, Oct. 2006.
[6] Jae-Seon Yoon, So-Young Yeo, Jee-Hoon Kim, and Hyoung-Kyu Song,
Cooperative Transmission Technique using Space Time Delay Code in
OFDMA Uplink System, IEICE Trans. on Communications, vol. E90-B
no. 5, pp. 1270-1273, May 2007.
[7] J. Niu, and I.-T. Lu, "Coded Cooperation on Block-Fading Channel in
OFDMA Systems," IEEE WCNC 2007, pp. 3466 - 3471, Mar. 2007.
[8] Jae-Seon Yoon, Hyoung-Muk Lim, Hyun-Jin Park, and Hyoung-Kyu
Song, "Performance Evaluation of Cooperative Communication for
OFDMA based Wireless Communication System," IEEE ICCT 2010, pp.
780 - 783, Nov. 2010.