MC-CDMA System Using Unitary Space-Time Modulation on Down-link Broadband Mobile Radio Communication
نویسندگان
چکیده
To solve the degradation of the BER performance of Space-Time Block Code (STBC)/MC-CDMA system when MC-CDMA system has large number of users, we propose Unitary Space-Time Modulation (USTM)/MC-CDMA system. USTM combines STBC and baseband modulation by employing unitary matrix. USTM is designed in order not to receive signals from different transmit antennas simultaneously at the receiver. In the proposed system, the effect of MUI can be reduced by employing USTM in comparison with STBC/MC-CDMA. Consequently, we show that the proposed system can improve the BER performance compared with STBC/MC-CDMA system when MC-CDMA system has large number of users.
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