SNR meaning in Military and Defence ?

Answer: What is Sonar mean?

Sonar (sound navigation and ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, measure distances (ranging), communicate with or detect objects on or under the surface of the water, such as other vessels. Two types of technology share the name "sonar": passive sonar is essentially listening for the sound made by vessels; active sonar is emitting pulses of sounds and listening for echoes. Sonar may be used as a means of acoustic location and of measurement of the echo characteristics of "targets" in the water. Acoustic location in air was used before the introduction of radar. Sonar may also be used for robot navigation, and SODAR (an upward-looking in-air sonar) is used for atmospheric investigations. The term sonar is also used for the equipment used to generate and receive the sound. The acoustic frequencies used in sonar systems vary from very low (infrasonic) to extremely high (ultrasonic). The study of underwater sound is known as underwater acoustics or hydroacoustics.

The first recorded use of the technique was by Leonardo da Vinci in 1490 who used a tube inserted into the water to detect vessels by ear. It was developed during World War I to counter the growing threat of submarine warfare, with an operational passive sonar system in use by 1918. Modern active sonar systems use an acoustic transducer to generate a sound wave which is reflected from target objects.

reference

Full Form	Category
School of Natural Resources	Academic & Science
St Nazaire	Airport Code
Sunair Electronics, Inc.	Business
Stiles & Riabokobylko	Business
Synergy Plus Limited	Business
Standard National Regulation	Computer Technology
Signal to Noise Ratio	Computing
Sequence Number Reset	Computing
Single Number Reach	General
Stake Not Returned	General
Single Number Rating	General
Schedule Negotiation Record	General
Special Needs Registry	General
Signal to Noise Rate	General
Single Noise Ratio	General
Senior National Representative	General
Steelers Nation Radio	General
Shannon Noise ratio	General
Saturday Night Racer	General
SHYAMNAGAR	Indian Railway Station
Streaks N' Recents	Internet
Snaps and recents	Internet
Society for Neuronal Regulation	Medical
Sonar	Military and Defence
Sub-net Relay	Military and Defence
Supernova Remnant	Physics Related
Sunflour Railroad	Regional
Sporting News Radio	Sports