Influence of dynamic binaural deformation on sound source orientation of short constant frequency pulses in bats

Hipposideridae bats exhibit complex dynamic ear deformations during echolocation. To investigate the impact of dynamic ear deformation on target localization, a bat-inspired dynamic binaural receiver was designed and constructed based on the synchronous binaural deformation observed in Hipposideros pratti bats. Constant-frequency short-pulse ultrasonic signals emitted by a sound source were collected from multiple spatial orientations. Subsequently, the time-frequency representation of the received sound source signal was extracted as input features, and a residual network-based deep learning regression model was employed for sound source orientation estimation. Finally, orientation errors in azimuth, elevation, and spatial orientation associated with the sound source were quantitatively analyzed. Comparative studies with static binaural and dynamic monaural receivers were conducted to examine the influence of dynamic ear deformation in bats on orientation accuracy. The results indicate that dynamic binaural deformation enhances sound source orientation accuracy and increases the proportion of high-accuracy localization intervals. Specifically, the proportion of elevation errors within 1° improved by 2.5%–13.9%. However, localization accuracy is frequency-dependent, exhibiting an approximately nonlinear negative correlation.