Question

Why is AM used for broadcasting in the communication systems?

• A. Its use avoids receiver complexity
• B. It is more immune to other modulation systems
• C. It requires less transmitting power
• D. No noise disturbances

Hint:

AM Broadcasting Advantages. Major advantage is the simplicity and low cost of receiver circuits (demodulation using envelope detectors). Disadvantages include susceptibility to noise and relatively inefficient power usage.

Answer 1

The Correct Option is A

Amplitude Modulation (AM) was one of the earliest modulation techniques used for radio broadcasting and remains in use (especially for long and medium wave bands)
Its primary advantage, particularly historically, is the simplicity of the receiver circuit required for demodulation
A simple envelope detector (often just a diode, capacitor, and resistor) can recover the audio signal from the AM carrier wave
This made AM radios relatively inexpensive and easy to manufacture
Compared to other modulation techniques like Frequency Modulation (FM): - AM is *less* immune to noise (noise primarily affects amplitude)
(Option 4 incorrect)
- FM receivers are more complex but offer better noise immunity
- AM often requires *more* transmitting power for similar coverage and quality compared to some other schemes, as much power resides in the carrier
(Option 3 incorrect)
- Immunity to other modulation systems (Option 2) is not a primary characteristic defining its use
The main reason for AM's widespread use in broadcasting, especially initially, was the simplicity and low cost of the receivers