Open AccessOn the Detection of Multiple‐Access Spatial Modulations
Author(s) -
Zhou Enzhi,
Hao Li
Publication year - 2017
Publication title -
chinese journal of electronics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.267
H-Index - 25
eISSN - 2075-5597
pISSN - 1022-4653
DOI - 10.1049/cje.2016.08.018
Subject(s) - linear subspace , maximization , detector , computational complexity theory , algorithm , decoding methods , computer science , projection (relational algebra) , subspace topology , spatial modulation , channel (broadcasting) , modulation (music) , detection theory , mathematics , mathematical optimization , mimo , telecommunications , artificial intelligence , physics , geometry , acoustics
The detection problem for the Multipleaccess Spatial modulations (M‐SM) is investigated in this paper, where multiple transmitters adopting spatial modulation communicate to the receiver at the same time. The optimal Maximum‐likelihood (ML) detection suffers from the high computational complexity, while Sphere decoding (SD) can not reduce the complexity effectively because of the multiple active antennas in M‐SM. In order to avoid the high complexity, a Space‐alternating generalized expectation‐maximization (SAGE) algorithm aided List‐projection (S‐LP) detector is proposed and applied to M‐SM systems. The received signal vector is firstly projected onto the subspaces spanned by the columns of channel matrices corresponding to the possible active antennas. Then some combinations of antenna indices with the largest projections are selected as candidate index sets, based on which, a modified SAGE algorithm is applied to update the candidate symbols. Both analysis and simulation results show that the proposed S‐LP detector achieves a near‐optimum performance with a significantly reduced complexity compared with ML and SD detection.