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What is the relation between carrier frequency and modulating signal?
Wiki User
∙ 10y ago
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.
Wiki User
∙ 10y ago
Wiki User
∙ 14y agoA carrier is a signal does exactly what it says. It carries a signal embedded within it to a radio receiver. The carrier signal is modulated by the music or speech signal to form a modulated carrier wave. Amplitude modulated, that is AM radio, makes the carrier wave voltage vary in sympathy with the audio modulator. In FM radio the carrier is frequency modulated, or varied in frequency by the modulator signal. Both radio types needs a carrier signal to get the modulating signal to the distant radio.
Wiki User
∙ 14y agoIn modulation, the carrier frequency is higher then modulating frequency, because you want the entire passband to be within the optimal performance range of the transmission media, usually an antenna. You also want to be able to share the system, such as with other channels.
Wiki User
∙ 12y agoFor the effective transmission of an EM wave the lenght of the antenna should be comparable with the wavelenght of the wave. The minimum lenght required for the antenna is l = wavelenhght/4. For a small frequency signal we need to use a very high antenna which is impractical.
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Is The carrier frequency is usually lower than the modulating frequency?
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).
In frequency modulation what happens to the bandwidth when you increase the modulating 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.
If the frequency in AM does not change then how are these sidebands formed?
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.
What will happen if frequency of modulating signal is greater than the carrier signal in amplitude modulation?
Then the signal will be the same amplitude.
Two signals of 2GHz and 4GHz are frequency modulated on same carrier 10?
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.
How do you calculate frequency range of double side band modulated signal?
Upper sideband = Carrier frequency + modulating frequencyLower sideband = Carrier frequency - modulating frequency
Webex bandwidth requirements?
Transmission bandwidth depends on modulating signal frequency and carrier frequency
Is it true that information can be carried on a carrier wave by changing or modulating either the amplitude or frequency?
in frequency modulation, frequency of carrier signal changes. so frequency variations of carrier convey all the information in frequency modulation.
When a carrier is phase modulated with an integrated modulating signal the resultant is?
It gives frequency modulated signal
Is The carrier frequency is usually lower than the modulating frequency?
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).
In frequency modulation what happens to the bandwidth when you increase the modulating 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.
In phase modulation the amount of phase shift in the carrier signal depends on the of the modulating signal and the rate of phase shift depends on the of the modulating signal?
Amplitude Frequency
If the frequency in AM does not change then how are these sidebands formed?
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.
What is the frequency deviation for frequency modulation?
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
How many AM broadcast stations can be accommodated in a 100 KHz bandwidth if the height frequency modulating a carrier is 5KHz?
40
What will happen if frequency of modulating signal is greater than the carrier signal in amplitude modulation?
Then the signal will be the same amplitude.
What is tone modulation?
Tone modulation through of modulating a carrier frequency using the charactoristics of a sound, its the method used for telephone
