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Only in an AM system. In an FM system, variations in carrier amplitude
are ironed out with hard limiting before demodulation.
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How does the signal change at the output AM out?
Your question doesn't give enough detail. AM typically stands for amplitude modulation. It is how AM radio works. A constant frequency is transmitted and the amplitude is varied to modulate the carrier wave with an information signal such as a song. Hence if you were examining how an AM signal changed you would see changes in the peak-to-peak voltage of the carrier frequency waveform.
How does the intelligence signal modulates the carrier?
There are three major types of modulation:AM, Amplitude Modulation, where the modulation signal is altering the amplitude of the carrier according to its own amplitude, normally this is done in the output stage. Therefor a strong audio signal is necessary at the same or a little less than the power of the carrier, never higher, because that will over modulate the carrier that will resort in distortion of the receiver output. AM is used in the lower band of the RF spectrum.FM, Frequency Modulation, where the frequency of the carrier is altered by the audio signal. When the amplitude of the audio is going higher the frequency go lower. Modulation happen at the oscillator stage, therefor a small audio signal is used to modulate the frequency. FM is normally used in the higher frequency range of the RF spectrum, 50MHz and up.FSK, Frequency-shift keying, used for data transmission, this type of modulation is simply, switching the carrier on and of, a high bit will switch the oscillator on and a low bit will switch it off, in some designs a low will be on and a high off.
Why normalization of message signal is necessary in conventional amplitude modulation?
to maintain the constant frequency and the phase parameters at the output
What is an amplitude modulation transmitter?
Amplitude Modulation, AM, is a technique where a high frequency carrier of constant amplitude and frequency is modulated by a lower frequency signal. This modulation varies the amplitude of the carrier, and the resultant modulated carrier is what is transmitted. A typical carrier in the standard AM broadcast band is 550 kilohertz to 1.6 megahertz, while the modulating signal is audio, in a range less than 20 kilohertz.Demodulation involves tuning the centerpoint of the carrier and detecting the envelope of modulation, often with a peak follower such as a diode, capacitor and resistor. Very simple AM radios can be built with only a few components, typically with less than six.While there are several demodulation techniques, by for the most common is the superhetrodyne technique. Since selectivity and sensitivity are opposing factors, the RF stage of such a receiver generally trades selectivity for sensitivity, simply boosting the gain with a middle of the road semi-broad band amplifier. Then this is mixed with a local oscillator that is tuned to be exactly 455 kilohertz away from the desired carrier frequency. The mixed signal then is shifted to a center point of 455 kilohertz.This is followed by a very steep skirt band pass filter, the IF stage, which filters out everything but the desired shifted carrier. This is where the selectivity comes in, and since the IF stage is tuned to only one frequency, it can be highly optimized. Actually, the IF stage is three stages, each tuned to slightly different frequencies, so that the response curve, while having steep skirts, and centered at 455 kilohertz, still has the bandwidth necessary to cover the audio range needed.The output of the IF stage is then demodulated using some kind of peak follower, and the output is the original signal.If you analyze the frequency domain of the modulated carrier, you discover that there is a carrier, and two side bands. The carrier contains no information, and consumes about 67% of the total power, while each side band carries the exact same information, but each is backwards to the other.This has led to improvements in design. Sometimes you can suppress the carrier prior to the final amplifier in the transmitter. This gives you the ability to put more power into the side bands. The down side is that the receiver is more complex, and has to regenerate the original carrier and mix it with the suppressed carrier signal before then mixing it for the downshift into the IF stage.You can take this even further, by suppressing both the carrier and one of the sidebands, since all of the signal is contained in both sidebands. Of course, this makes the receiver even more complex.Some CB and Amateur radios are single sideband suppressed carrier, simply known as SSB, in order to boost range. Most broadcast stations are double sideband non-suppressed carrier, simply known as AM, in order to simplify the receiver. Different areas of the world use slightly different terminology, such as SSB-SC, but the intent is the same.
What is amplitude distortion?
Amplitude distortion occurs in an electronic signal when the power of the amplifier is not great enough to carry the sine wave to its intended peak amplification. If you look at the wave form of a amplitude distorted output signal, it would look like someone had neatly sliced off the top of a hill. Though amplitude distortion is usually an undesired result, the effect is sometimes used intentionally for audio applications, such as a distorted rock guitar which gives that crunchy rock sound.
Should demodulated output ideally depend on carrier amplitude?
In an AM system, definitely. In any other system, amplitude variations are intentionally ironed out, by hard limiting, before demodulation.
How does the signal change at the output AM out?
Your question doesn't give enough detail. AM typically stands for amplitude modulation. It is how AM radio works. A constant frequency is transmitted and the amplitude is varied to modulate the carrier wave with an information signal such as a song. Hence if you were examining how an AM signal changed you would see changes in the peak-to-peak voltage of the carrier frequency waveform.
How does the intelligence signal modulates the carrier?
There are three major types of modulation:AM, Amplitude Modulation, where the modulation signal is altering the amplitude of the carrier according to its own amplitude, normally this is done in the output stage. Therefor a strong audio signal is necessary at the same or a little less than the power of the carrier, never higher, because that will over modulate the carrier that will resort in distortion of the receiver output. AM is used in the lower band of the RF spectrum.FM, Frequency Modulation, where the frequency of the carrier is altered by the audio signal. When the amplitude of the audio is going higher the frequency go lower. Modulation happen at the oscillator stage, therefor a small audio signal is used to modulate the frequency. FM is normally used in the higher frequency range of the RF spectrum, 50MHz and up.FSK, Frequency-shift keying, used for data transmission, this type of modulation is simply, switching the carrier on and of, a high bit will switch the oscillator on and a low bit will switch it off, in some designs a low will be on and a high off.
Is carrier signal present at output of double side band suppressed carrier?
No, the carrier signal is not present at the output of double side band suppressed carrier. That is what suppressed carrier means. However, the receiver has enough information to regenerate the carrier if need be. The advantage of suppressed carrier mode is that more power can be deployed to the signal-carrying portion of the modulated carrier.
Why amplitude modulation is called as collector modulation?
amplitude modulation using collector modulator gives:More symmetrical envelope• Higher power efficiency• Higher output power• Need higher amplitude modulatingsignal
What is the main issue with output devices?
It would depend on what the output device was
What will be the output of differentiator if the input is sine wave?
a phase shifted sine wave of a different amplitude.
What is the relationship of the input amplitude of the voltage at input and output in the half wave rectifire?
The input and output amplitudes should be (approximately) the same.The amplitude of a periodic waveform is defined to be the difference between its average (or reference) and "peak" value. In the United States, the electricity from a standard wall plug is a "120 V" sine wave. This means that relative to ground, the waveform is varying from about -170V to +170V (the "120" number is the RMS value), so the amplitude is 170V. If you use this as the input to a half-wave rectifier, the output will lose either the positive-going or negative going swings; the output will go, for example, from 0 to +170V. Measured from the 0V reference, the output amplitude is 170V.
What are the parameters that the output voltage and current waveforms depend on it?
waveforms depend on it
What are the parameters that the output voltage and current waveforms depend on?
waveforms depend on it
What is master oscillator?
it generates the carrier frequency of the output after passing a signal.
Why do you get a staircase output in the quantization process of Pulse Code Modulation?
quantisation is the assigning the signal amplitudes to some levels,if amplitude is 4.8 we treat it as 5 and when it is 3.1 the output value is 3 thus we are assigning the amplitude to some reference levels thus corresponds to different amplitudes we get different quantisation output hence we get staircase signal
