Which type of modulation is primarily used in AM radio broadcasting?

Amplitude Modulation (AM) is the technique used in AM radio broadcasting because it conveys information by varying the amplitude of the carrier wave. In AM, the audio signal (which includes speech, music, or other sounds) modulates the strength or amplitude of the carrier frequency. This allows the audio information to be transmitted over long distances effectively.

The characteristics of AM make it particularly suitable for broadcasting over the medium wave and shortwave bands, as it can be easily detected by receivers and offers good coverage, especially in rural areas. Since AM radio stations often operate at lower frequencies compared to FM stations, the ability to amply modulate the signals is critical for clarity and reach for the audience.

Other modulation types, such as Phase Modulation and Frequency Modulation, while used in various forms of communication, are not suitable for AM broadcasting. Pulse Modulation is typically employed in digital communication systems, which also do not involve traditional AM broadcasting methods. Thus, Amplitude Modulation remains the standard for AM radio.