Self-adapting Cyclic Delay Diversity System
نویسندگان
چکیده
Cyclic Delay Diversity (CDD) is a simple and efficient space-time diversity technique. It can be used in OFDM and DFT-Spread-OFDM. The traditional CDD has low complexity and system overhead, however, also has some limitations on performance and is sensitive to propagation environment. In this paper, two improved CDD scheme including open-loop and closeloop strategies for uplink and downlink of EUTRA LTE are introduced. Compared with the conventional method, the new schemes can obtain higher performance and less sensitivity to environment. KeywordsCyclic Delay Diversity (CDD), orthogonal frequency-division multiplexing (OFDM), DFT-Spread-OFDM (DFT-S-OFDM), self-adapting, transmit diversity
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