Why do we modulate a signal during transmission and demodulation during receiving?

Reasons for Modulation Modulation of signal is important to prevent mixing of message signals from different transmitters and makes it easier to tune to the desired signal. For reliable and effective communication over long distance i.e. minimizing the signal losses during transmission.

Why do we modulate a signal for transmission?

We modulate a signal for transmission because baseband transmission has many limitations which can be overcome using modulation. In the process of modulation, the baseband signal is translated i.e., shifted from low frequency to high frequency. This frequency shift is proportional to the frequency of carrier.

Why modulation demodulation is needed when transmitting data over a radio system?

The modulated signal is then transmitted over a channel, after which the original information-bearing signal is recovered through a process of demodulation. In order to prevent mutual interference, each user’s information signal is modulated onto an assigned carrier of a specific frequency.

Why is it necessary to modulate a baseband signal on a carrier signal before transmitting it?

8.4. But a baseband signal cannot be transmitted over a radio link or a satellite because this would require a large antenna to radiate the low-frequency spectrum of the signal. Hence the baseband signal spectrum must be shifted to a higher frequency by modulating a carrier with the baseband signal.

How does modulation and demodulation work?

– In modulation, the original message signal is mixed with a carrier wave whose parameters are required to be changed. In demodulation, the combination of carrier and message signal are separated from each other, to have an original information signal.

What is the importance of demodulation?

Demodulation is extracting the original information-bearing signal from a carrier wave. A demodulator is an electronic circuit (or computer program in a software-defined radio) that is used to recover the information content from the modulated carrier wave.

Why is modulation necessary?

The signals within 20 Hz to 20 kHz frequency range can travel only a few distances. To send the message signal, the length of the antenna should be a quarter wavelength of the used frequency. Thus, modulation is required to increase the frequency of the message signal and to enhance its strength to reach the receiver.

Why modulation and demodulation is needed?

At the broadcasting station, modulation is done to transmit the audio signal over larger distances to a receiver. When the modulated wave is picked up by the radio receiver, it is necessary to recover the audio signal from it. This process is accomplished in the radio receiver and is called demodulation.