%0 Journal Article
%T A Design Method of Noncoherent Unitary Space-Time Codes
%A Li Peng
%A Qiuping Peng
%A Lingling Yang
%J Int'l J. of Communications, Network and System Sciences
%P 430-435
%@ 1913-3723
%D 2011
%I Scientific Research Publishing
%R 10.4236/ijcns.2011.47051
%X We generalized an constructing method of noncoherent unitary space time codes (N-USTC) over Rayleigh flat fading channels. A family of N-USTCs with <i>T</i> symbol peroids, <i>M</i> transmit and <i>N</i> receive antennas was constructed by the exponential mapping method based on the tangent subspace of the Grassmann manifold. This exponential mapping method can transform the coherent space time codes (C-STC) into the N-USTC on the Grassmann manifold. We infered an universal framework of constructing a C-STC that is designed by using the algebraic number theory and has full rate and full diversity (FRFD) for t symbol periods and same antennas, where <i>M, N, T, t</i> are general positive integer. We discussed the constraint condition that the exponential mapping has only one solution, from which we presented a approach of searching the optimum adjustive factor ¦Á<sub>opt</sub> that can generate an optimum noncoherent codeword. For different code parameters <i>M, N, T, t</i> and the optimum adjustive factor ¦Á<sub>opt</sub>, we gave the simulation results of the several N-USTCs.
%K Noncoherent Uintary Space-Time Codes (N-USTC)
%K Coherent Space-Time Codes (C-STC)
%K Grassmann Manifold
%K Degree of Freedom
%K Exponenatial Map
%K Full Rate and Full Diversity (FRFD)
%U http://www.scirp.org/journal/PaperInformation.aspx?PaperID=5821