Acoustic Sensing
Acoustic sensing used a microphone in a missile. The characteristic frequency of an aircraft engine is filtered and triggers the detonation. This principle was applied in British experiments with bombs, anti-aircraft missiles, and airburst shells (circa 1939). Later it was applied in German anti-aircraft missiles, which were mostly still in development when the war ended.
The British used a Rochelle salt microphone and a piezoelectric device to trigger a relay to detonate the projectile or bomb's explosive.
Naval mines can also use acoustic sensing, with modern versions able to be programmed to "listen" for the signature of a specific ship.
Read more about this topic: Proximity Fuze
Famous quotes containing the word sensing:
“Something was still there, that something that distinguishes an artist from a performer: the revealing of self. Here I be. Not for long, but here I be. In sensing her mortality, we sensed our own.”
—Studs Terkel (b. 1912)