A Simple Cooperative Cyclic Delay Diversity in Wireless Networks

Cyclic delay diversity (CDD) was introduced to obtain spatial diversity in multi-input multi-output (MIMO) system. In practice, terminals are difficult to have multiple antennas due to high cost or limited size. Accordingly, the cooperative scheme has recently emerged and given considerable attention. In this paper, CDD is incorporated into the wireless cooperative communication system, in which each terminal has single antenna. The proposed cooperative CDD scheme is compared with cooperative orthogonal space time block code (STBC). Cooperative CDD attains generally worse performance than cooperative STBC from orthogonal design, but cooperative CDD can be easily applied with an arbitrary number of relays and do not require additional complexity at both transmitter and receiver.