Modulation and demodulation are components of modems that convert analog signals to digital signals and vice versa. The process of converting digital to analog is known as modulation, and the reverse of modulation is known as demodulation. Analogue signals are continuous, whereas digital signals are discrete, or change abruptly. In this article, we will explain modulation and demodulation, as well as the differences between them.

What is Modulation?

The method of converting information to signal for transferring the digital signals over an electronic medium. In terms of computer networks, we say that the conversion of digital to analog signals. The frequency transmission in modulation goes from low to high.

for example- a TV without a setup box in that case TV operates through the operator. The other example is that we all use microphones to record the audio clip the voice used in audio is human voice which is in the form of Analog signals, the computer converts the human voice into the digital signal and vice-versa. In simple words, we say that modulation is the method of superimposing high frequency to low frequency.

Working of Modulation

fig: Modulation

The working of modulation is the method of superimposing high frequency over low frequency. The circuit we used in the modulation is the modulator. In modulation, they have carrier signals and modulated signals. In carrier signal, the signal contains no information but they have a phase, amplitude, and frequency. In modulated signal, it is the combination of Carrier signal and modulation.

Types of Modulation

1. Amplitude Modulation: This modulation technology is to transfer voice over radio. It occurs when the carrier signal is changed but phase and frequency stay constant.

2. Phase Modulation: In phase modulation, the frequency is directly proportional to the Phase. When there is a fluctuation in Phase, the frequency also reflects variation.

3. Frequency Modulation: In Frequency modulation, the frequency of the carrier signal is changed while the phase and amplitude of the signal are not changed.

Advantages of Modulation

• It reduces the height of the Antenna.
• In modulation, there is no mixing of signal.
• It provides flexibility for adjusting the bandwidth.
• It enhance the range of communication.
• It reduces noise transmission.
• Modulation is transmission efficient that means signal transmit over long distance.

Disadvantages of Modulation

• Modulation have complexity issues.
• The equipment cost is more.
• It is not useful for high bandwidth.
• There is a loss of power.

What is Demodulation?

The method of extracting the data from modulation is called demodulation. It recovers the signal that is generated from the modulated signal. It generated the output in the form of sound waves, pictures, and binary data. The other definition we say in terms of computer network is the conversion of analog signal to digital signal. The frequency transmission in demodulation going from high to low. for example, The TV with a set-top box in the case set-top box operates the TV.

Working of Demodulation

fig: Demodulation

The working of demodulation is the process of recovery of the information that is generated from the modulated wave. The circuit demodulator is used in the block diagram of demodulation. In demodulation, the receiver receives the signal in modulation through the receiver Antenna then recovers the data by using a demodulator and gives the output in the form of sound.

Types of Demodulation

1. Amplitude Modulation: In Amplitude modulation, we used rectifiers to demodulate the signal that is generated from the modulation signal.

2. Frequency Modulation: In Frequency modulation, we know that the frequency modulation of the carrier signal is changed while the phase and amplitude of the signal are not changed after that demodulation technique recovers the original signal that is generated from the modulated wave. In that case, we use Phase-locked loops for demodulation.

3. Phase Modulation: We learned in phase modulation, the frequency is directly proportional to the Phase. When there is a fluctuation in Phase, the frequency also reflects variation after that demodulation technique recovers the original signal that is generated from the modulated wave. In that case, we use a Phase detector for demodulation.

Advantages of Demodulation

• It helps to improve the original signal.
• It improve the Amplitude, frequency and phase modulation signals.
• Demodulation improve the signal reliability.

Disadvantages of Demodulation

• Demodulation have high power consumption.
• It is a complex process.
• The equipment cost is expensive.

Diference Between Modulation and Demodulation