How do bat echolocation calls help bats judge the direction of an object?

Bats determine the direction of an object through echolocation by analyzing the returning echoes of their high-frequency sound pulses.1

To judge direction, bats rely on the following mechanisms:

• Frequency Analysis: Evidence suggests that the multiple frequencies found in frequency-modulated (FM) or harmonic pulse patterns are crucial for determining target direction. When a bat receives three or more frequencies, it compares the relative intensities of these signals as they arrive at each ear.1
• Auditory Specialization: Bats possess large external ears, or pinnae, which act as efficient collectors and resonators for high-frequency sounds. These ears are often freely movable, allowing the bat to incline or rotate them to better capture incoming signals.12
• Neural Processing: The bony auditory complex is frequently isolated from the skull, which enhances the bat's ability to compare signals between the two ears. The central nervous system then integrates this auditory information to pinpoint the object's location in space.12