Tognola G, Grandori F, Ravazzani P
Department of Biomedical Engineering, Polytechnic of Milan, Italy.
IEEE Trans Biomed Eng. 1998 Jun;45(6):686-97. doi: 10.1109/10.678603.
Time-frequency distribution methods are being widely used for the analysis of a variety of biomedical signals. Recently, they have been applied also to study otoacoustic emissions (OAE's), the active acoustic response of the hearing end organ. Click-evoked otoacoustic emissions (CEOAE's) are time-varying signals with a clear frequency dispersion along with the time axis. Analysis of CEOAE's is of considerable interest due to their close relation with cochlear mechanisms. In this paper, several basic time-frequency distribution methods are considered and compared on the basis of both simulated signals and real CEOAE's. The particular structure of CEOAE's requires a method with both a satisfactory time and frequency resolution. Results from simulations and real CEOAE's revealed that the wavelet approach is highly suitable for the analysis of such signals. Some examples of the application of the wavelet transform to CEOAE's are provided here. Applications range from the extraction of normative data from adult and neonatal OAE's to the extraction of quantitative parameters for clinical purposes.
时频分布方法正被广泛用于分析各种生物医学信号。最近，它们也被应用于研究耳声发射（OAE），即听觉末梢器官的主动声学响应。短声诱发耳声发射（CEOAE）是随时间变化的信号，沿时间轴具有明显的频率离散。由于CEOAE与耳蜗机制密切相关，对其进行分析具有相当大的意义。本文基于模拟信号和真实的CEOAE，对几种基本的时频分布方法进行了考虑和比较。CEOAE的特殊结构需要一种具有令人满意的时间和频率分辨率的方法。模拟和真实CEOAE的结果表明，小波方法非常适合分析此类信号。这里提供了小波变换应用于CEOAE的一些示例。应用范围从从成人和新生儿OAE中提取标准数据到为临床目的提取定量参数。
