Echo Delay and Overlap with Emitted Orientation Sounds and Doppler-shift Compensation in the Bat, Rhinolophus ferrumequinum
b'The compensation of Doppler-shifts by the bat, Rhinolophusferrumequinum,\\nfunctions only when certain temporal relations between the echo\\nand the emitted orientation sound are given. Three echo configurations\\nwere used:\\na) Original orientation sounds were electronically Doppler-shifted and\\nplayed back either cut at the beginning (variable delay) or at the end (variable\\nduration) of the echo.\\nb) Artificial constant frequency echoes with variable delay or duration\\nwere clamped to the frequency of the emitted orientation sound at different\\nDoppler-shifts.\\nc) The echoes were only partially Doppler-shifted and the Doppler-shifted\\ncomponent began after variable delays or had variable durations.\\nWith increasing delay or decreasing duration of the Doppler-shifted echo\\nthe compensation amplitude for a sinusoidally modulated + 3 kHz Dopplershift\\n(modulation rate 0.08 Hz) decreases for all stimulus configurations\\n(Figs. 1, 2, 3).\\nThe range of the Doppler-shift compensation system is therefore limited\\nby the delay due to acoustic travel time to about 4 m distance between\\nbat and target. In this range the overlap duration of the echo with the\\nemitted orientation sound is always sufficiently long, when compared with\\ndata on the orientation pulse length during target approach from Schnitzler\\n(1968) (Fig. 5).'