Downlink site diversity with frequency-domain equalization for DS-CDMA cellular systems
نویسندگان
چکیده
Abstract In DS-CDMA high speed wireless signal transmissions, the transmission performance degrades due to frequency selective fading. The use of frequency-domain equalization (FDE) can significantly improve the transmission performance. However, the local average received signal power slowly varies due to distance-dependent path loss and shadowing loss according to the movement of a mobile user. This local average signal power variation causes the performance degradation particularly when a user is located close to the cell edge where the received signal power is weak and the interference from other cells is strong. To improve the transmission performance, the well-known site diversity can be used in addition to FDE. In this paper, we present downlink site diversity for a cellular DS-CDMA with FDE. The DS-CDMA downlink capacity is evaluated by computer simulation and compared to the MC-CDMA downlink capacity. Keyword DS-CDMA,Frequency-domain equalization,Site diversity,Link capacity
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