Why modulation needed

No need to find colleges in other sites, this is the best site in India to know about any colleges in India. Home QnA Home Explain briefly why modulation is needed at all?? Get answers from students and experts Ask. Answer later. Hello, Modulation is the process of changing the parameters of the carrier signal, in accordance with the instantaneous values of the modulating signal.

Need for Modulation The baseband signals are incompatible for direct transmission. Advantages of Modulation The antenna used for transmission, had to be very large, if modulation was not introduced. Following are some of the advantages for implementing modulation in the communication systems. Antenna size gets reduced.

No signal mixing occurs. Communication range increases. Multiplexing of signals occur. If every signal gets its own frequency range, then we can transmit multiple signals simultaneously over a single channel, all using different frequency ranges.

Another reason to modulate a signal is to allow the use of a smaller antenna. Modulation shifts the baseband signal up to a much higher frequency, which has much smaller wavelengths and allows the use of a much smaller antenna. Think about your car radio. There are more than a dozen or so channels on the radio at any time, each with a given frequency: Each channel gets a certain range usually about 0. Modulation makes it all possible, because it allows us to send voice and music which are essential baseband signals over a bandpass or "Broadband" channel.

A sine wave at one frequency can be separated from a sine wave at another frequency or a cosine wave at the same frequency because the two signals are "orthogonal". There are other sets of signals, such that every signal in the set is orthogonal to every other signal in the set.

The diagram shows the amplified modulated wave after superimposing the message signal with the carrier signal. Phase Modulation: It is the type of modulation in which the phase of the base signal changes while superimposing it with a carrier signal.

Frequency Modulation: By superimposing the base signal with the carrier signal having a different frequency, but the same amplitude, if the frequency of the base signal modifies or modulates, then it is said to be frequency modulation. The baseband signals transmitted by the sender are not capable of direct transmission.

The strength of the message signal should be increased so that it can travel longer distances. This is where modulation is essential. The most vital need of modulation is to enhance the strength of the signal without affecting the parameters of the carrier signal.

Modulation has removed the necessity for using wires in the communication systems. It is because modulation is widely used in transmitting signals from one location to another with faster speed. Thus, the modulation technique has helped in enhancing wireless communication systems. Modulation and its types prevent the interference of the message signal from other signals.

In the process of modulation, the baseband signal is translated i. When the transmission occurs over free pace, the antennae radiate the signal out and receiver receives it. In order to operate efficiently, antennae need to be in order of the magnitude of wavelength of the transmitted signal. This length of the antenna can be built easily and this example clearly shows us how hugely the process of modulation is enabling communication systems.

This is a point from the practical side of things. Suppose you are transmitting the baseband signal as it is to a receiver, say your friends phone.