Real-domain decoder for full-rate full-diversity STBC with multidimensional constellations

H. Lee, J. Cho, J.-K. Kim, I. Lee
2009 IEEE Transactions on Communications  
In this letter, we present a new maximum likelihood (ML) decoding algorithm for space time block codes (STBCs) that employ multidimensional constellations. We start with a lattice representation for STBCs which transforms complex channel models into real matrix equations. Based on the lattice representation, we propose a new decoding algorithm for quasiorthogonal STBCs (QO-STBC) which allows simple ML decoding with performance identical to the conventional ML decoder. Multidimensional rotated
more » ... nstellations are constructed for the QO-STBCs to achieve full diversity. As a consequence, for quasi-orthogonal designs with an arbitrary number of transmit antennas N (N ≥ 4) , the proposed decoding scheme achieves full rate and full diversity while reducing the decoding complexity from O(M N/2 c ) to O(M N/4 c ) in a Mc-QAM constellation. Index Terms-Diversity methods, maximum likelihood decoding (MLD), multidimensional rotated constellations, space-time block codes (STBC).
doi:10.1109/tcomm.2009.0901.070056 fatcat:dj4jkes43bhr5mrlcotc3lhln4