自然梯度盲源分离加速收敛的衡量依据

Measurement Basis of Accelerating Convergence of Natural Gradient Blind Source Separation

所有信号均有既定的峭度累积量,无论是固定步长自然梯度盲源分离或变步长自然梯度盲源分离,从分离信号峭度累积量变化的角度看,观察分离信号峭度累积量随步长迭代(固定步长迭代,或变步长迭代)过程的前后之差值e(k)变化,可衡量自然梯度盲源分离稳定加速收敛的观察指标就存在于e(k)曲线的变化特征中.仿真实验结果表明:e(k)曲线迭代开始阶段(变化率接近0)和变化部分的集中程度是两个重要观察指标.当衡量构成与自然梯度盲源分离输出程度紧密关联的稳定加速方法的有效性时,该特征指标就是一个参考依据.

All signals have a given kurtosis cumulant, so whether it is fixed step natural gradient blind source separation or variable step natural gradient blind source separation, the stable and accelerated convergence of natural gradient blind source separation existing in the variation characteristics of e(k) curve can be observed through the change of kurtosis cumulant of separated signal with the difference e(k) before and after step iteration(fixed step iteration or variable step iteration) from the perspective of the change of kurtosis cumulant of separated signal.The simulation results show that the initial stage of e(k) curve iteration(the change rate is close to 0) and the concentration of the change part are two important observation indexes.This characteristic index is a reference when measuring the effectiveness of the stable acceleration method closely related to the output degree of natural gradient blind source separation.