Frequency Modulation

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Frequency Modulation

Frequency Modulation (FM) is a modulation technique in which the frequency of the carrier signal is varied in proportion to the amplitude of the information-carrying signal. This results in a signal that is less susceptible to noise and other interference.

What does Frequency Modulation mean?

Frequency Modulation (FM) is a modulation technique that transmits information by varying the frequency of a carrier wave. It is used in a wide range of applications, including radio broadcasting, Telecommunications, and radar.

In FM, the instantaneous frequency of the carrier wave is varied in proportion to the amplitude of the modulating Signal. This results in a signal that has a wider bandwidth than the modulating signal, but is more resistant to noise and interference.

The Key advantage of FM over other modulation techniques is its ability to reject noise. This is because the frequency of the carrier wave is not affected by noise, so the information can be recovered even if the signal is degraded.

Applications

FM is used in a wide range of applications, including:

  • Radio broadcasting: FM is the most common type of modulation used for radio broadcasting. It provides high-quality audio with minimal noise and interference.
  • Telecommunications: FM is used in a variety of telecommunications applications, including Mobile phones, satellite communications, and microwave links. It provides reliable and secure communication over long distances.
  • Radar: FM is used in radar systems to measure the speed and distance of objects. It provides accurate and reliable measurements, even in challenging conditions.

History

The history of FM can be traced back to the early days of radio broadcasting. In 1922, Edwin Armstrong developed a system of FM broadcasting that was far superior to the AM (amplitude modulation) systems that were in use at the time. Armstrong’s system provided high-quality audio with minimal noise and interference, but it was not widely adopted until the 1940s.

During World War II, FM was used by the military for secure communications. After the war, FM broadcasting became more popular, and by the 1960s, it was the dominant form of radio broadcasting in the United States.

Today, FM is still widely used in a variety of applications. It is the most common type of modulation used for radio broadcasting, and it is also used in telecommunications, radar, and other applications.