A theorem for wide bandwidth echolocation systems
Abstract
Echolocation systems are unavoidably subject to rangevelocity ambiguities. Although the total amount (volume) of ambiguity increases with increasing signal bandwidth, it is shown here that ambiguity density decreases with increasing bandwidth. This result, which is stated in the paper as a theorem, means that for systems observing targets with restricted relative velocities, the effective volume of ambiguity decreases as the bandwidth is increased. It is suggested that this may help one to understand the performance of mammals with advanced echolocation senses, since increasing the bandwidth not only reduces effective ambiguity volume but also improves range resolution and reverberation suppression. For a given bandwidth the effective ambiguity volume is minimized if the energy spectrum of the echolocation signal is uniform throughout the band.
 Publication:

Journal of Sound Vibration
 Pub Date:
 May 1971
 DOI:
 10.1016/0022460X(71)904846
 Bibcode:
 1971JSV....16..223B