Question

is a process that causes a shift in the range of frequencies in a signal

• A. Moderation
• B. Modulation
• C. Demodulation
• D. Measurement

Hint:

Think of the carrier wave as a "truck" and the message signal as the "cargo." Modulation is the process of loading the cargo onto the truck so it can travel at high speeds to its destination.

Answer 1

The Correct Option is B

1. Defining Modulation:

Modulation is the process of varying one or more properties of a high-frequency "carrier" wave (such as its amplitude, frequency, or phase) in accordance with a low-frequency "message" signal.

2. Frequency Shifting: The fundamental effect of modulation is that it shifts the message signal from its original low-frequency baseband range to a much higher frequency range centered around the carrier frequency. This "frequency shift" allows many different signals to be transmitted simultaneously through the same medium (like air or cable) by assigning each a different carrier frequency.

3. Types of Modulation:

• AM (Amplitude Modulation): Changes the carrier's strength.

• FM (Frequency Modulation): Changes the carrier's speed/timing.

• PM (Phase Modulation): Changes the carrier's starting position in its cycle.
The reverse process, which extracts the original message back at the receiver, is called

Demodulation.