If the modulating system is AM (Amplitude Modulation) then the amplitude of the carrier wave changes with the amplitude of the modulation. On a specrum analyser that shows up as frequency sidebands. If the frequency of the carrier waves depends on the amplitude of the modulating signal that is called FM (frequency modulation). On a spectrum analyser that shows up as sidebands also.
when the frequency is low , energy will be obviously low. To increase the energy of the signal we need to increase the frequency. This is achieved by multiplying the message signal with the carrier signal (with high frequency).
Bandwidth increases as a function of both modulating frequencyand deviation. As deviation increases, pairs of sidebands are generated, each equal to fc+m and fc-m, fc+2m, fc-2m etc. where fc = the carrier frequency and m = the modulating frequency. Increasing modulation (frequency deviation) will change the level of each of the sideband pairs - and the carrier, which at times falls to zero.
The process of changing the amplitude of the "carrier" so as to add information to it (modulation) doesn't change the frequency of the carrier. But it does create energy at two other newfrequencies.The new frequencies are equal to (carrier frequency) plus and minus (the modulating frequency). These are referred to as the upper and lower sidebands.The upper sideband is an exact copy of the modulating signal, but with every component of it shifted up by an amount equal to the carrier frequency. The lower sideband is a mirror image of the upper sideband, with every frequency component in it reflected about the carrier frequency.
Then the signal will be the same amplitude.
Definition: In FM technique, the frequency of the carrier signal changes according to the instantaneous amplitude of the modulating signal. Hence, the frequency of the modulating signal is of irrelevance here and the devition from "fc" will be dependent on the amplitude of the same. considering 2GHz and 4GHz to be digital signal the ratio would be 1:1.
Upper sideband = Carrier frequency + modulating frequencyLower sideband = Carrier frequency - modulating frequency
The three frequency components of an amplitude modulation (AM) wave are the carrier frequency, the upper sideband frequency (carrier frequency + modulating frequency), and the lower sideband frequency (carrier frequency - modulating frequency). These components are responsible for carrying the signal information in an AM wave.
Transmission bandwidth depends on modulating signal frequency and carrier frequency
in frequency modulation, frequency of carrier signal changes. so frequency variations of carrier convey all the information in frequency modulation.
It gives frequency modulated signal
when the frequency is low , energy will be obviously low. To increase the energy of the signal we need to increase the frequency. This is achieved by multiplying the message signal with the carrier signal (with high frequency).
Bandwidth increases as a function of both modulating frequencyand deviation. As deviation increases, pairs of sidebands are generated, each equal to fc+m and fc-m, fc+2m, fc-2m etc. where fc = the carrier frequency and m = the modulating frequency. Increasing modulation (frequency deviation) will change the level of each of the sideband pairs - and the carrier, which at times falls to zero.
The wavelength of a carrier wave is the distance between two consecutive crests or troughs of the wave. It is inversely proportional to the frequency of the wave, so higher frequency waves have shorter wavelengths. In telecommunications, carrier waves are used to transmit information by modulating their properties.
Amplitude Frequency
The process of changing the amplitude of the "carrier" so as to add information to it (modulation) doesn't change the frequency of the carrier. But it does create energy at two other newfrequencies.The new frequencies are equal to (carrier frequency) plus and minus (the modulating frequency). These are referred to as the upper and lower sidebands.The upper sideband is an exact copy of the modulating signal, but with every component of it shifted up by an amount equal to the carrier frequency. The lower sideband is a mirror image of the upper sideband, with every frequency component in it reflected about the carrier frequency.
Deviation ratio: In a frequency modulation system, the ratio of the maximum frequency deviation of the carrier to the maximum modulating frequency of the system under specified conditions
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