What is Amplitude Modulation in Communication System? | New Topic [2024]

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Author Name: Arun Paul.

What is Amplitude Modulation in Communication System?

Amplitude Modulation (AM) is a technology used in electrical communication to convey information across a radio carrier wave. It operates by changing the strength (amplitude) of the carrier wave in accordance to the data being transmitted. This modulation differs from others such as Frequency Modulation (FM) and Phase Modulation (PM), which change the frequency or phase of the carrier wave.

Here are we describe that how AM works –

• Carrier Wave: A constant signal of a given frequency that serves as the basis for modulation.
• Modulating Signal: The actual information or message signal to be sent, such as voice, music, or data.

Bandwidth for AM Signal

An AM signal’s overall bandwidth is equal to twice the modulating signal’s maximum frequency. For example, if the modulating signal has a maximum frequency of 5 kHz, the AM signal will need a bandwidth of 10 kHz.

Advantages in AM

Here are some advantages of this type of modulation –

1. AM transmitters and receivers are relatively easy and inexpensive to manufacture.
2. AM signals can travel considerable distances, particularly at night when they reflect off the ionosphere.

Disadvantages in AM

Here are some disadvantages of this type of modulation –

1. AM signals are more susceptible to noise and interference than FM.
2. AM is less efficient in terms of power consumption since it sends duplicated information (the carrier), which contains no relevant information.