rahuld.exe said:In the amplitude modulation equation,
V=(Ec+Ei*coswt)coswt
I don't understand why the instantaneous value of information signal is used. Shouldnt it be peak value as that would give the maximum value (amplitude)?
The equation for amplitude modulation is given by:
S(t) = Ac[1 + m(t)] cos(2πfct)
where S(t) is the modulated signal, Ac is the carrier amplitude, m(t) is the modulating signal, and fc is the carrier frequency.
The modulation index is calculated by dividing the peak amplitude of the modulating signal by the peak amplitude of the carrier signal. This can be represented as:
μ = Am/Ac
where Am is the peak amplitude of the modulating signal, and Ac is the peak amplitude of the carrier signal.
The purpose of amplitude modulation is to combine a low-frequency signal, such as an audio signal, with a high-frequency carrier signal in order to transmit information through a medium, such as radio waves. This allows for efficient use of bandwidth and the ability to transmit multiple signals simultaneously.
Changing the modulation index can affect the amplitude modulated signal in several ways. If the index is increased, the amplitude of the modulated signal will also increase, which can result in distortion and potential interference with other signals. If the index is decreased, the amplitude of the modulated signal will decrease, potentially resulting in a weaker signal that is more susceptible to noise.
Amplitude modulation has many practical applications, such as in radio broadcasting, television broadcasting, and voice communication systems. It is also used in radar systems for detecting and tracking objects, and in instrumentation for measuring and analyzing signals. Additionally, it is used in some types of digital communication, such as amplitude-shift keying (ASK) and quadrature amplitude modulation (QAM).