Sonar uses sound waves to work and is mainly used in water; radar uses electromagnetic waves to work and radar acts in the air. Moreover, the transmitting and receiving devices of sonar and radar are also different.
How it works
1. Sonar
As an acoustic detection equipment, active sonar was first put into use in the UK, but the British This device was called "ASDIC" (Submarine Detector), and the Americans called it "SONAR". Later, the British also accepted this name.
Because the attenuation rate of electromagnetic waves in water is very high and cannot be used as a signal source for detection, sound waves have become the most widely used method to detect artificial objects under the water. Whether they are submarines or surface ships, they all use systems derived from this technology to detect underwater objects or use them as a basis for navigation.
2. Radar
Radar (RADAR) is the abbreviation and transliteration of the English "Radio Detection and Ranging". It emits electromagnetic energy into space in a directional manner. By receiving the radio waves reflected by objects in space, the direction, height and speed of the object can be calculated, and the shape of the object can be detected.
History
1. Sonar technology has a history of more than 100 years. It was invented by Lewis Richardson of the British Navy in 1906. The first sonar he invented was a passive listening device mainly used to detect icebergs?[4] This technology began to be used on the battlefield during World War I to detect submarines lurking under the water. These sonar can only passively listen to sound and are passive sonar, or "hydrophones".
2. The emergence of radar was due to the fact that during World War II, when Britain and Germany were at war, Britain urgently needed a radar (technology) that could detect metal objects in the air to help search for German aircraft in anti-air raid warfare. During World War II, radar technology had already appeared with ground-to-air, air-to-ground (search) bombing, air-to-air (interception) fire control, and identification of friend or foe.