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1概述诱发电位(EP)的估计和检测为隐含的生理状况提供了有价值的信息,因此这些信号被广泛应用于研究和临床领域中。EP测量中的一项困难是信噪比(SNR)较低,因而需采用SNR增强技术。测量噪声源主要是放大器的热电压噪声和放大器电流噪声流经电极-组织界面时形成的电极-组织界面噪声。传统的SNR增强是通过把用一对电极及单通道测量所获得的诱发响应记录作总集平均实现的,它通过提高参加平均的记录数N来提高SNR,但这是以增加测量时间为代价的。本文将介绍一种不用增加测量时间就能改善EP测量SNR
1 Overview The estimation and detection of evoked potentials (EPs) provide valuable information for implicit physiological conditions and are therefore widely used in research and clinical settings. One of the difficulties in EP measurement is the low signal-to-noise ratio (SNR) that necessitates the use of SNR enhancement techniques. The sources of measurement noise are mainly the electrode-tissue interface noise that is formed when the amplifier’s thermal voltage noise and amplifier current noise flow through the electrode-tissue interface. The traditional SNR enhancement is achieved by recording an average of evoked responses obtained with a pair of electrodes and single channel measurements as a whole, which increases SNR by increasing the number of recordings participating in the average N, but at the expense of increasing the measurement time of. This article describes an approach to improving EP measurement SNR without increasing measurement time