Title :
Distributed space-time code designs via Cayley transform
Author_Institution :
Dept. of Electr. & Comput. Eng., Univ. of Alberta, Edmonton, AB, Canada
Abstract :
Distributed space-time coding achieves full diversity in wireless relay networks without channel information at the relays. This paper is on the design of specific distributed space-time codes. By Cayley transform, the design of unitary matrices is transformed to that of Hermitian matrices. Gradient-descent method is used in the optimization to find codes that are ¿close¿ to orthogonal designs, which is known to be optimal in both coding gain and diversity. The proposed code design method can be used for networks with any relays and transmission rate. The optimized codes are adaptive to the information symbol constellation. Simulation shows that the designed codes achieve full diversity, and outperform the random code and other existing distributed space-time codes.
Keywords :
Hermitian matrices; gradient methods; orthogonal codes; radio networks; transforms; Cayley transform; Hermitian matrices; distributed space-time code designs; gradient-descent method; information symbol constellation; orthogonal designs; unitary matrices; wireless relay networks; Computer networks; Conferences; Design methodology; Design optimization; Distributed computing; Relays; Space time codes; Transmitters; Vectors; Wireless networks;
Conference_Titel :
Computational Advances in Multi-Sensor Adaptive Processing (CAMSAP), 2009 3rd IEEE International Workshop on
Conference_Location :
Aruba, Dutch Antilles
Print_ISBN :
978-1-4244-5179-1
Electronic_ISBN :
978-1-4244-5180-7
DOI :
10.1109/CAMSAP.2009.5413264
