Simplest Sonar

SONAR stands for Sound Navigation Ranging, and is a technique for determining the distance and direction of objects by acoustic means. Although SONAR is usually associated with navigation ranging under water, it may also be used to good effect in air – for instance, to detect boats in a fog.

SONAR may be divided into three categories.

1. Active SONAR

Projects a sound wave and waits for the echo, which these days can be analysed with great sophistication.

2. Passive SONAR

Projects no sound, but analyses incoming sound, e.g. to identify a passing submarine; and a third category of

3. SONAR transmits and receives messages across an “acoustic path”.

The SONAR described here is an active system, with the most basic functionality – it simply reports the existence of an object within a 1 metre (1 yard) range. In fact, with just five components, this has to be the simplest SONAR in the world!

Related Schematics