Distributed differential space-time coding for wireless relay networks
IEEE Transactions on Communications
Distributed space-time coding is a cooperative transmission scheme proposed for wireless relay networks. With this scheme, antennas of the distributive relays work as transmit antennas of the sender and generate a space-time code at the receiver. When the transmit power is infinitely large, it achieves the maximum diversity. Although the scheme needs no channel information at relays, it requires full channel information at the receiver. In this paper, based on distributed space-time coding, we
... ce-time coding, we propose a differential transmission scheme, which requires channel information at neither relays nor the receiver. As distributed space-time coding can be seen as the counterpart of space-time coding in the network setting, this scheme is the counterpart of differential space-time coding. Compared to distributed coherent space-time coding, the differential scheme is 3dB worse. In addition, we show that Alamouti, square real orthogonal, and Sp(2) codes, which are originally proposed for multiple-antenna systems, can be used differentially in networks with corresponding numbers of relays.