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[Author] Ryo HAYAKAWA(2hit)

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  • Error Recovery for Massive MIMO Signal Detection via Reconstruction of Discrete-Valued Sparse Vector

    Ryo HAYAKAWA  Kazunori HAYASHI  

     
    PAPER-Communication Theory and Systems

      Vol:
    E100-A No:12
      Page(s):
    2671-2679

    In this paper, we propose a novel error recovery method for massive multiple-input multiple-output (MIMO) signal detection, which improves an estimate of transmitted signals by taking advantage of the sparsity and the discreteness of the error signal. We firstly formulate the error recovery problem as the maximum a posteriori (MAP) estimation and then relax the MAP estimation into a convex optimization problem, which reconstructs a discrete-valued sparse vector from its linear measurements. By using the restricted isometry property (RIP), we also provide a theoretical upper bound of the size of the reconstruction error with the optimization problem. Simulation results show that the proposed error recovery method has better bit error rate (BER) performance than that of the conventional error recovery method.

  • Lattice Reduction-Aided Detection for Overloaded MIMO Using Slab Decoding

    Ryo HAYAKAWA  Kazunori HAYASHI  Megumi KANEKO  

     
    PAPER-Wireless Communication Technologies

      Vol:
    E99-B No:8
      Page(s):
    1697-1705

    In this paper, we propose an overloaded multiple-input multiple-output (MIMO) signal detection scheme with slab decoding and lattice reduction (LR). The proposed scheme firstly splits the transmitted signal vector into two parts, the post-voting vector composed of the same number of signal elements as that of receive antennas, and the pre-voting vector composed of the remaining elements. Secondly, it reduces the candidates of the pre-voting vector using slab decoding and determines the post-voting vectors for each pre-voting vector candidate by LR-aided minimum mean square error (MMSE)-successive interference cancellation (SIC) detection. From the performance analysis of the proposed scheme, we derive an upper bound of the error probability and show that it can achieve the full diversity order. Simulation results show that the proposed scheme can achieve almost the same performance as the optimal ML detection while reducing the required computational complexity.