Science · 6 pages · 12 min

How sonar times an echo

Send a ping, time the return, and halve the trip because the sound went both ways.

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From the opening

Sonar times an echo by sending a short sound pulse and measuring how long until it returns. The sound went to the target and back, so the one-way distance is half of that path. The opening covers half the round trip, why sound speed is local, and false ranges from extra bounces.

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Inside

Half the round trip
Why sound speed is local
False ranges from extra bounces
The same clock in radar
Where the idea stops applying
A distinction worth keeping

Sources

Echo ranging and round-trip time of flight
Sound speed in seawater and its dependence on conditions

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How sonar times an echo

From the opening

Inside

Sources

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