Modulation is the PROCESS of varying the characteristics of a high frequency carrier signal (i.e. amplitude, frequency or phase) in accordance with the LOW frequency message signal. When a signal is transmitted, NOISE gets added through the environment, channel/medium of communication, transmitter/receiver incapability etc. which sometimes adversely affects the low frequency signal transmitted (WITHOUT modulation) resulting in decaying of information to be sent. Thus, the low frequency baseband signal is modulated over a high frequency carrier signal to minimize the EFFECT of noise for effective transmission of information even over long distances.

Modulation is the process of varying the characteristics of a high frequency carrier signal (i.e. amplitude, frequency or phase) in accordance with the low frequency message signal. When a signal is transmitted, noise gets added through the environment, channel/medium of communication, transmitter/receiver incapability etc. which sometimes adversely affects the low frequency signal transmitted (without modulation) resulting in decaying of information to be sent. Thus, the low frequency baseband signal is modulated over a high frequency carrier signal to minimize the effect of noise for effective transmission of information even over long distances.