Download : Soundscapes 75 MB. Sonar, short for Sound Navigation and Ranging , is helpful for exploring and mapping the ocean because sound waves travel farther in the water than do radar and light waves.
NOAA scientists primarily use sonar to develop nautical charts , locate underwater hazards to navigation, search for and map objects on the seafloor such as shipwrecks, and map the seafloor itself. There are two types of sonar—active and passive. Active sonar transducers emit an acoustic signal or pulse of sound into the water. Radar and lidar LY-dahr rely on echoes, too. Instead, these two technologies use radio waves or light waves, respectively. Both are examples of electromagnetic radiation.
Detection or navigation refers to locating objects. Depending on the technology, these objects may be underwater, in the air, on or below the ground, or even in space. For that measurement, time plays an important role. Lidar, radar and sonar systems all include timing devices. Their clocks record the length of time needed for a wave to travel to an object and back.
The farther the distance, the longer it takes for an echo to return. Air traffic controllers use radar to spot aircraft in the sky. Police use it to detect speeders. The principle of operations of both sonar and radar is same but uses different wave types.
Radio waves in the frequency range from 3 MHz to GHz. Use of jamming EM waves , but it is unaffected by birds. Weather radar, search radar, automotive radar, ground penetrating radar,.
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