Joint Space-Time Transmit Diversity and Minimum Mean Square Error Equalization for MC-CDMA with Antenna Diversity Reception

SUMMARY In this paper, the space time transmit diversity (STTD) decoding combined with minimum mean square error (MMSE) equalization is presented for MC-CDMA downlink and uplink in the presence of multiple receive antennas. The equalization weights that minimize the MSE for each subcarrier are derived. From computer simulation, it was found that the BER performance of STTD decoding combined with MMSE equalization and Mr-antenna diversity reception using the weights derived in this paper provides the same diversity order as 2Mr-antenna receive diversity with MMSE equalization but with 3 dB performance penalty and is always better than that with no diversity. The uplink BER performance can also be improved with STTD, but the error floor still exists. However, with 2-receive antennas in addition to 2-antenna STTD, the BER floor can be reduced to around 10 −5 even for the uplink.

[1]  Gregory E. Bottomley,et al.  Jakes fading model revisited , 1993 .

[2]  R. Kimura,et al.  Comparison of OFDM and multicode MC-CDMA in frequency selective fading channel , 2003 .

[3]  Jean-Paul M. G. Linnartz,et al.  Multi-Carrier Cdma In Indoor Wireless Radio Networks , 1994 .

[4]  Hiroyuki Atarashi,et al.  Variable Spreading Factor Orthogonal Frequency and Code Division Multiplexing (VSF-OFCDM) , 2002 .

[5]  Fumiyuki Adachi,et al.  Joint Antenna Diversity and Frequency-Domain Equalization for Multi-Rate MC-CDMA , 2003 .

[6]  W. Root,et al.  An introduction to the theory of random signals and noise , 1958 .

[7]  E-L. Kuan,et al.  Overview of Multicarrier CDMA , 2004 .

[8]  Steven D. Gray,et al.  Transmit diversity in 3G CDMA systems , 2002, IEEE Commun. Mag..

[9]  Americo Brajal,et al.  Orthogonal multicarrier techniques applied to direct sequence spread spectrum CDMA systems , 1993, Proceedings of GLOBECOM '93. IEEE Global Telecommunications Conference.

[10]  Siavash M. Alamouti,et al.  A simple transmit diversity technique for wireless communications , 1998, IEEE J. Sel. Areas Commun..

[11]  Ali N. Akansu,et al.  Multicarrier CDMA systems with transmit diversity , 2000, Vehicular Technology Conference Fall 2000. IEEE VTS Fall VTC2000. 52nd Vehicular Technology Conference (Cat. No.00CH37152).

[12]  Mamoru Sawahashi,et al.  Pilot Channel Assisted MMSE Combining in Forward Link for Broadband OFCDM Packet Wireless Access , 2002, IEICE Trans. Fundam. Electron. Commun. Comput. Sci..