The maximum amplitude of an amplitude-modulated wave is found to be 15V while its minimum amplitude is found to be 3V. The modulation index is:
Correct Answer: 0.67
Approach Solution - 1
Given: and
Therefore, and
So, [where m=modulation index]
Hence, the correct answer is .
Approach Solution -2
The process of mounting or superimposing a very low-frequency signal over a high-frequency signal or carrier wave is known as modulation.
There are generally three types of modulation
- Amplitude Modulation: If the amplitude of the carrier wave changes in accordance with the amplitude of the very low-frequency signal, while the frequency and phase of the carrier wave remain unchanged, then the modulation is known as amplitude modulation.
- Frequency Modulation: If the frequency of a carrier wave changes in accordance with the frequency of the very low-frequency signal, while the amplitude and phase of the carrier wave remain unchanged, then the modulation is known as frequency modulation.
- Phase Modulation: If the phase of a carrier wave changes in accordance with the phase of the very low-frequency signal, while the amplitude and frequency of the carrier wave remain unchanged, then the modulation is known as phase modulation.
Modulation Index
The modulation index determines the quality of the amplitude-modulated wave. The formula for the modulation index is given by
Modulation index, ma = (Emax - Emin) / (Emax + Emin)
Where
- Emax = maximum amplitude of the amplitude modulated wave
- Emin = minimum amplitude of the amplitude modulated wave
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Concepts Used:
Communication Systems
A system that describes the information exchange between two points is called the communication system. The transmission and reception process of information is called communication. The major elements of communication are such as:
- The Transmitter of information
- Channel or medium of communication
- The Receiver of information
Examples Of Communication Systems:
The following are the examples of communication systems:
- Internet
- Public Switched Telephone network
- Intranet and Extranet
- Television
Types Of Communication Systems:
Turning on Signal specification or technology, the communication system is categorized as follows:
- Analog technology communicates data as electronic signals of differing frequencies or amplitude. For instance Broadcast and telephone transmission.
- In Digital technology, the data are created and processed in two states: High (represented as 1) and Low (represented as 0). Also this technology stores and transmits data in the form of 1's and 0's.
Elements of a Communication System:
