Performance of Transmit Time Selection Diversity in Multipath Fading Channels
نویسندگان
چکیده
We examine transmit time selection diversity (TTSD) concept, where downlink transmission is suspended if the received SNR in the mobile station falls below a given threshold. In case of FDD systems, this requires a fast feedback channel from mobile to base like the one in the FDD WCDMA system. Bit error probability formulas are derived showing that TTSD is able to provide gains up to several decibels when compared to continuous transmission. Results also indicate that if the wireless environment already provides diversity — as in the case of multipath fading channels and transmit diversity — gains against continuous transmission are smaller.
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