
Abstract
The greater horseshoe bat (Rhinolophus ferrumequinum) emits echolocation sounds consisting of a long constant-frequency (CF) component preceeded and followed by a short frequency-modulated (FM) component. When an echo returns with an upward Doppler-shift, the bat compensates for the frequency-shift by lowering the emitted frequency in the subsequent orientation sounds and stabilizes the echo image. The bat can accurately store frequency-shift information during silent periods of at least several minutes. The stored frequency-shift information is not affected by tone bursts delivered during silent periods without an overlap with an emitted orientation sound. The system for storage of Doppler-shift information has properties similar to a sample and hold circuit with sampling at vocalization time and with a rather flat slewing rate for the stored frequency information.
Item Type: | Journal article |
---|---|
Faculties: | Biology |
Subjects: | 500 Science > 570 Life sciences; biology |
URN: | urn:nbn:de:bvb:19-epub-3155-7 |
Item ID: | 3155 |
Date Deposited: | 08. Apr 2008, 13:34 |
Last Modified: | 29. Apr 2016, 08:55 |