Human echolocation : waveform analysis of tongue clicks.

Some blind individuals have the ability to detect and classify objects in complex scenes by using echolocation based on ‘tongue clicks’. A waveform analysis of the tongue clicks collected from three blind individuals is presented who use tongue-click based echolocation on a daily basis. It is found that the tongue clicks are wideband signals and that that the spectrum of clicks varies within and between individuals. However, by using the wideband ambiguity function, it is found that all of the clicks from three different individuals share some common characteristics.