Title :
Diversity-multiplexing tradeoff optimal codes for OFDM-based asynchronous cooperative networks
Author :
Lu, Hsiao-Feng Francis
Author_Institution :
Dep. of Commun. Eng., Nat. Chung-Cheng Univ., Chia-yi
Abstract :
An asynchronous cooperative network where different time delays among nodes exist is considered in this paper. With OFDM modulation, it is first shown that the diversity-multiplexing tradeoff (DMT) achieved by the non-orthogonal selection decode-and-forward (NSDF) protocol for this network is the same as that for the synchronous one. In sharp contrast to the currently available complicated approximately universal "matrix" codes, a systematic construction of an extremely simple "vector" code is proposed. Given the transmitted codeword vector, the same codeword will be sent by all nodes during transmission, hence it will greatly reduce the complexities of relay deployment and decoding. Furthermore, it is proved that the proposed scheme achieves the optimal DMT of the NSDF protocol for this asynchronous cooperative network.
Keywords :
OFDM modulation; delays; multiplexing; protocols; OFDM modulation; OFDM-based asynchronous cooperative networks; diversity-multiplexing tradeoff optimal codes; matrix codes; nonorthogonal selection decode-and-forward protocol; systematic construction; time delays; transmitted codeword vector; vector code; Cellular networks; Decoding; Delay effects; Electronic mail; Frame relay; Local oscillators; OFDM modulation; Performance analysis; Protocols; Wireless sensor networks;
Conference_Titel :
Information Theory, 2008. ISIT 2008. IEEE International Symposium on
Conference_Location :
Toronto, ON
Print_ISBN :
978-1-4244-2256-2
Electronic_ISBN :
978-1-4244-2257-9
DOI :
10.1109/ISIT.2008.4595278