One-User/One-Group Soft-Decision Aided Multiuser Detection for 2D Spread MC DS-CDMAs

Hoang-Yang Lu, I-Hsuan Lai

Dept. of Electrical Engineering, National Taiwan Ocean University, Keelung City.

DOI: 10.4236/cn.2013.53B2023                

Abstract

We consider the uplink of a multiuser, multiple-input multiple-output (MIMO), frequency-time-domain spread, multi- carrier (MC), direct sequence code division multiple access (DS-CDMA) system. As other CDMA-like systems, the multiple access interference (MAI) effect still exists in such an MC DS-CDMA system. To mitigate the MAI effect, we propose user-based and group-based layered detection schemes. Specifically, to enable a trade-off between the performance and the computational complexity, the schemes only use one user's/group's soft decisions for user-based/ group-based layered detection. The results of simulations demonstrate that the proposed schemes outperform existing approaches, and their computational complexity is modest.

Keywords

Multiuser detection, MC DS-CDMA, VBLAST, MIMO

Conflicts of Interest

The authors declare no conflicts of interest.

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