Tognola G, Ravazzani P, Grandori F
Center of System Theory (CNR), Polytechnic of Milan, Italy.
Br J Audiol. 1995 Jun;29(3):153-60. doi: 10.3109/03005369509086592.
There is a need for methods capable of increasing the detectability of transient-evoked otoacoustic emissions (TEOAE). Detection of an emission is based commonly on either visual inspection and cross-correlation between replicate recordings or cross-spectral analysis. Performance of these methods is obviously influenced by the residual noise level. Residual noise is often of low frequency and can be reduced by digital off-line filtering. For this purpose, an optimal high-pass filtering technique is proposed. Cross-correlation between replicates of TEOAEs was used to determine the cut-off frequency that maximizes the signal-to-noise (S/N) ratio. This is shown in a series of responses characterized by various S/N ratios. Data have been scored both visually and with quantitative methods before and after the use of high-pass filtering. The capability to detect the signal was increased with only a marginal decrease in the total power of the emissions.
需要能够提高瞬态诱发耳声发射（TEOAE）可检测性的方法。耳声发射的检测通常基于目视检查以及重复记录之间的互相关或互谱分析。这些方法的性能显然受到残余噪声水平的影响。残余噪声通常为低频，可通过数字离线滤波来降低。为此，提出了一种最优的高通滤波技术。利用TEOAE重复记录之间的互相关来确定使信噪比（S/N）最大化的截止频率。这在一系列具有不同信噪比的响应中得到了体现。在使用高通滤波之前和之后，已通过目视和定量方法对数据进行了评分。信号的检测能力得到了提高，而发射的总功率仅略有下降。
