TY - GEN
T1 - Transmit diversity for down-link MC-CDMA based on energy spreading transform
AU - Hwang, Taewon
AU - Li, Ye
PY - 2007
Y1 - 2007
N2 - In this paper, we investigate transmit diversity for MC-CDMA down-link mobile communications. We apply recently developed energy spreading transform (EST) in MCCDMA systems to pick up diversity in frequency-selective wireless channels and to improve signal detection performance. It is shown by computer simulation that the required Eb/NO's for a 10-2 bit-error-rate (BER) are improved by about 5 dB for both an indoor channel and an urban channel compared with a MC-CDMA system without an EST. For a system with two transmit antennas and Alamouti's code, the required E b/NO for an EST based MC-CDMA system is improved by 2.7 dB for an indoor channel and 3.3 dB for an outdoor channel compared with a MC-CDMA system without an EST. For a system with multiple transmit antennas, symbol shuffling scheme, together with an EST, has been proposed for transmit diversity. Even though symbol shuffling scheme alone is not as good as Alamouti's code, it can be combined with Alamouti's code to reach matched filter bound (MFB) for systems with over four transmit antennas. Comparison of our transmit-diversity approach with the widely used MMSE detection for MC-CDMA systems is also provided.
AB - In this paper, we investigate transmit diversity for MC-CDMA down-link mobile communications. We apply recently developed energy spreading transform (EST) in MCCDMA systems to pick up diversity in frequency-selective wireless channels and to improve signal detection performance. It is shown by computer simulation that the required Eb/NO's for a 10-2 bit-error-rate (BER) are improved by about 5 dB for both an indoor channel and an urban channel compared with a MC-CDMA system without an EST. For a system with two transmit antennas and Alamouti's code, the required E b/NO for an EST based MC-CDMA system is improved by 2.7 dB for an indoor channel and 3.3 dB for an outdoor channel compared with a MC-CDMA system without an EST. For a system with multiple transmit antennas, symbol shuffling scheme, together with an EST, has been proposed for transmit diversity. Even though symbol shuffling scheme alone is not as good as Alamouti's code, it can be combined with Alamouti's code to reach matched filter bound (MFB) for systems with over four transmit antennas. Comparison of our transmit-diversity approach with the widely used MMSE detection for MC-CDMA systems is also provided.
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U2 - 10.1109/WCNC.2007.118
DO - 10.1109/WCNC.2007.118
M3 - Conference contribution
AN - SCOPUS:36348962906
SN - 1424406595
SN - 9781424406593
T3 - IEEE Wireless Communications and Networking Conference, WCNC
SP - 612
EP - 616
BT - 2007 IEEE Wireless Communications and Networking Conference, WCNC 2007
T2 - 2007 IEEE Wireless Communications and Networking Conference, WCNC 2007
Y2 - 11 March 2007 through 15 March 2007
ER -