Sun Biao, Zhao Wenfeng, Zhu Xinshan
School of Electrical Engineering and Automation, Tianjin University, Tianjin 300072, People's Republic of China.
J Neural Eng. 2017 Jun;14(3):036018. doi: 10.1088/1741-2552/aa630e. Epub 2017 Feb 27.
Data compression is crucial for resource-constrained wireless neural recording applications with limited data bandwidth, and compressed sensing (CS) theory has successfully demonstrated its potential in neural recording applications. In this paper, an analytical, training-free CS recovery method, termed group weighted analysis [Formula: see text]-minimization (GWALM), is proposed for wireless neural recording.
The GWALM method consists of three parts: (1) the analysis model is adopted to enforce sparsity of the neural signals, therefore overcoming the drawbacks of conventional synthesis models and enhancing the recovery performance. (2) A multi-fractional-order difference matrix is constructed as the analysis operator, thus avoiding the dictionary learning procedure and reducing the need for previously acquired data and computational complexities. (3) By exploiting the statistical properties of the analysis coefficients, a group weighting approach is developed to enhance the performance of analysis [Formula: see text]-minimization.
Experimental results on synthetic and real datasets reveal that the proposed approach outperforms state-of-the-art CS-based methods in terms of both spike recovery quality and classification accuracy.
Energy and area efficiency of the GWALM make it an ideal candidate for resource-constrained, large scale wireless neural recording applications. The training-free feature of the GWALM further improves its robustness to spike shape variation, thus making it more practical for long term wireless neural recording.
对于数据带宽有限的资源受限无线神经记录应用而言,数据压缩至关重要,而压缩感知(CS)理论已成功证明其在神经记录应用中的潜力。本文提出一种用于无线神经记录的解析、无需训练的CS恢复方法,称为分组加权分析[公式:见正文]-最小化(GWALM)。
GWALM方法由三部分组成:(1)采用分析模型来增强神经信号的稀疏性,从而克服传统合成模型的缺点并提高恢复性能。(2)构建一个多分数阶差分矩阵作为分析算子,从而避免字典学习过程并减少对先前采集数据的需求以及计算复杂度。(3)通过利用分析系数的统计特性,开发一种分组加权方法来提高分析[公式:见正文]-最小化的性能。
在合成数据集和真实数据集上的实验结果表明,所提出的方法在尖峰恢复质量和分类准确率方面均优于基于CS的现有方法。
GWALM的能量和面积效率使其成为资源受限的大规模无线神经记录应用的理想候选方法。GWALM的无需训练特性进一步提高了其对尖峰形状变化的鲁棒性,从而使其在长期无线神经记录中更具实用性。