This is how some blind people are able to echolocate like bats
From: New Scientist - 09/06/2017
By: Clare Wilson

Some people who are blind can echolocate like bats, using mouth clicks to
sense and understand the environment around them. Now we are beginning to
understand the acoustics behind this skill.

Many people who are blind get information from ambient echoes, but only a few
make their own noises to echolocate. Some, like Daniel Kish in California,
are so proficient they can sketch a room after clicking their way around it,
or even go mountain biking along unfamiliar routes. "You can tell a tree from
a post and from a human," says Kish.

We already knew that this ability involves some brain areas used for vision
in sighted people. Kish, who has been blind almost from birth, thinks he
experiences the sensations as something akin to images. "There's a real
palpable experience of the image as a spatial representation - here are
walls, here are the corners, here is the presence of objects."

Now Lore Thaler of Durham University, UK, and her team have carried out the
first in-depth acoustic analysis of mouth clicks. They worked with Kish and
two other blind echolocators.

Read the entire article at:
https://www.newscientist.com/article/mg23531421-600-this-is-how-some-blind-people-are-able-to-echolocate-like-bats

Links:
Human bat uses echoes and sounds to see the world
https://www.newscientist.com/article/mg22630204-100-human-bat-uses-echoes-and-sounds-to-see-the-world

Echo vision: The man who sees with sound
https://www.newscientist.com/article/mg20227031-400-echo-vision-the-man-who-sees-with-sound

Neural Correlates of Natural Human Echolocation in Early and Late Blind
  Echolocation Experts
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0020162

Lore Thaler
https://www.dur.ac.uk/psychology/staff/?id=9604

Mouth-clicks used by blind expert human echolocators – signal description and
  model based signal synthesis
http://journals.plos.org/ploscompbiol/article?id=10.1371/journal.pcbi.1005670

This is how some blind people are able to echolocate like bats - Extended
  Version
https://www.newscientist.com/article/2145962-this-is-how-some-blind-people-are-able-to-echolocate-like-bats

Blind children should be allowed to learn to echolocate like me
https://www.newscientist.com/article/2145969-blind-children-should-be-allowed-to-learn-to-echolocate-like-me