数字信号处理_自适应滤波.pptVIP

BIOMEDICAL DIGITAL SIGNAL PROCESSING ④自相关(autocorrelation):用R峰对准相关技术，选取最大相关的一个模板进行对消（称为最大相关对消、最大相关提取或最大相关滤波)。可以证明相关最大时输出功率最小(满足MSE或LMS准则) 。 ③在同一ECS上（自参考）有哪些信誉好的足球投注网站(最大导数和最大值双重有哪些信誉好的足球投注网站技术)母体R波，定位R峰。 ②自参考(autoreference)：在母体ECS上，选取2-3个无胎儿心电重迭的母体QRS波作为模板(称为多模板技术，保存三个模板数组)。 ①高采样率：选较高的采样频率，如１千～2千Hz，以使R波峰漂移较小； 按以下步骤完成： ⑤自适应(autoadapotation):调整对消因子W (乘一个比例因子) ，使输出功率最小： min E[y2] = E[s2] + minE[(n0－ζ)2] (11.4) min E[y2] = E[s2] + minE[(n0－Wn1)2] (11.4a) ?The area of electrical impedance pneumography has used adaptive filtering to solve the problem of cardiogenic artifact (ZCG). Such artifact can arise from electrical impedance changes due to blood flow and heart　volume changes. This can lead to a false interpretation of breathing. 11.4.3　Cardiogenic artifact 11.4.3 心源性伪迹 在肺阻抗(信息提取)技术(ZCG)领域中，常用自适应滤波解决心源性伪迹问题。该伪迹产生于血流和心脏体积变化引起的电阻抗变化。这可导致假呼吸的解释（误判为有呼吸）。 When monitoring for infant apnea, this might result in a failure to alarm. Sahakian et al. proposed using an adaptive LMS algorithm to extract the cardiogenic impedance component so as to achieve the best estimate of the respiratory impedance component. 当监护婴儿呼吸（暂停，即是否有呼吸）时，可导致不报警。 Sahakian等建议用自适应LMS算法提取心源性阻抗分量以达到呼吸阻抗分量的最佳估计。 为建立心源性伪迹模型，他们建立了一个与含窦性节律异常的ECS中的QRS复合波同步的模板。心源性伪迹与心室收缩同时发生但有延迟，因此该ECS模板可用来导出和消除ZCG. To model the cardiogenic artifact, they created a template synchronized to the QRS complex in an ECS that included sinus arrhythmia. Cardiogenic artifact is synchronous with but delayed from ventricular systole, so the ECS template can be used to derive and eliminate the ZCG. 1.现有提取诱发电位的迭加平均技术的基本假设 11.4.4　诱发电位提取中的自适应干扰对消技术 I. THE basic HYPOTHESIS for TRANDITIONALLY extracting EP (evoked potential ) with superposition-averaging EP is a deterministic signal without any variation such as frequency, amplitude and latency ( i. e. initial phase ) in each stimulation. Electroencephalo-signal (EES), as a background interference, power interference and so on are the white noise. (1)EP是确定性信号，在每次刺激时频率、幅度和潜伏期都不会变化。 (2)作为背景干扰的脑电信号,工频干扰