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arXiv · 2104.08064

Efficient QAM Signal Detector for Massive MIMO Systems via PS-ADMM Approach

Quan Zhang·Jiangtao Wang·Yongchao Wang
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Abstract

In this paper, we design an efficient quadrature amplitude modulation (QAM) signal detector for massive multiple-input multiple-output (MIMO) communication systems via the penalty-sharing alternating direction method of multipliers (PS-ADMM). Its main content is as follows: first, we formulate QAM-MIMO detection as a maximum-likelihood optimization problem with bound relaxation constraints. Decomposing QAM signals into a sum of multiple binary variables and exploiting introduced binary variables as penalty functions, we transform the detection optimization model to a non-convex sharing problem; second, a customized ADMM algorithm is presented to solve the formulated non-convex optimization problem. In the implementation, all variables can be solved analytically and in parallel; third, it is proved that the proposed PS-ADMM algorithm converges under mild conditions. Simulation results demonstrate the effectiveness of the proposed approach.

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BibTeXRIS

Quan Zhang, Jiangtao Wang, Yongchao Wang. 2021-04-16. Efficient QAM Signal Detector for Massive MIMO Systems via PS-ADMM Approach. https://arxiv.org/abs/2104.08064

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