Explain the different types of modulation! In the digital era, transferring the data is very easy for example audio, video files are sent in the form of electrical signals to the desired device or a person. For a lay man it sounds easy, but actually it is not as its complexity is very tough. Modulation is the important factor with respect to communication system any data to be transferred as to be modulated for sending them over long distance without any disturbance or loss of data. Define Modulation It is the process of changing the features of the wave to be transmitted with message signal on a higher frequency. Data signals, voice, and, video are converted into high frequency signal also called as carrier wave. This wave AC or DC or pulse chain which relies on the application used. A carrier wave signal is basically a high frequency sine wave. Reason for the use of modulation in communication For the purpose of transmission the message frequency signal is increased to a range. If you consider signal
transmission there are lots of sources ready to transmit via common medium so if everything is transferred in the same frequency then it will lead to disturbance and interference. Therefore modulation concept is used over here for instance the sound file is transferred at a particular modulation frequency and from the receiver it is decoded from the given set of frequency transmissions. The antenna size is also another factor which is inversely proportional to the radiation frequency signal. If the size of the signal is just 6khz then it is not usable therefore it has to be modulated and increased thereby reducing the size of the antenna. It is not possible to send low frequency signal over longer distance and therefore modulation is important over here. For avoiding any disturbance and allocating more channels to the users, modulation is mandatory. Different Types of Modulation There are different types of modulation they are�
Analog Digital The baseband information is converted into Radio Frequency Signals in both the techniques and the only difference is RF signals are in continuous state in Analog and discrete state in digital. Analog Modulation For carrier wave a continuous sine wave is used over here for modulating message signal over data. There are three types of Analog modulation they are: Amplitude Modulation: Only the amplitude of the carrier wave is varied with respect to the message signal. It requires greater bandwidth and more power. Frequency Modulation: Frequency of the carrier wave is varied with respect to the message signal. Modulation index and modulating frequency governs the efficiency and bandwidth. Phase Modulation: Phase of the carrier wave is varied with respect to message signal but frequency is also varied with respect to phase therefore this also comes under frequency modulation. Drawback: Disturbance till the receiver end.
Digital Modulation: It is preferred a lot when compared to analog modulation. The main benefit lack of disturbance, available bandwidth. After the conversion of message signal from analog to digital format it is modulated using a carrier wave. Here also there are three types of digital modulation amplitude, frequency, continuous phase modulation, Trellis coded modulation, and phase. The professional courses for electrical engineers will help you to learn a lot about electrical design.