McLellan G
University of Wyoming, Laramie, WY 82071, USA.
Biomed Sci Instrum. 2001;37:69-74.
The pallid bat (Antrozous pallidus) is a member of a small class of bats known as gleaners. These bats use echolocation to avoid obstacles in flight while using passive listening to localize terrestrial prey. The echolocation pulses are 60-30 KHz downward frequency modulated sweeps that last 3-5 milliseconds. The prey-generated sounds are broadband noise transients in the 5-35 KHz range [1]. The frequency components of these sounds are beyond the range of commonly available sound cards, but the availability of fast, low-cost computers makes it possible to use host-based digital signal processing techniques to generate more complex sound patterns using existing equipment. The new capabilities allow new types and combinations of behaviorally relevant sounds to be generated, permitting the functions and topology of the auditory cortex to be mapped with increased detail. This paper describes the algorithms used to generate the amplitude and frequency modulated tones and band-pass filtered noise signals used as stimulus sounds.
苍白洞蝠（Antrozous pallidus）是一小类被称为食虫蝠的蝙蝠成员。这些蝙蝠在飞行时利用回声定位来避开障碍物，同时通过被动聆听来定位地面猎物。回声定位脉冲是频率向下调制的扫描信号，频率范围为60 - 30千赫兹，持续3 - 5毫秒。猎物发出的声音是5 - 35千赫兹范围内的宽带噪声瞬变信号[1]。这些声音的频率成分超出了普通声卡的范围，但快速、低成本计算机的出现使得利用基于主机的数字信号处理技术，使用现有设备生成更复杂的声音模式成为可能。这些新功能允许生成行为相关声音的新类型和组合，从而能够更详细地绘制听觉皮层的功能和拓扑结构。本文描述了用于生成用作刺激声音的调幅和调频音调以及带通滤波噪声信号的算法。
