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What is amplitude modulation and frequency modulation and difference between them?
Wiki User
∙ 13y ago
Both angle and amplitude modulation are involved in radio wavelength patterns. Angle modulation is where the modulating wave manipulates the angle of a sine-wave carrier. The two types of angle modulation include frequency and phase modulation. On the other hand, Amplitude modulation is the strength behind carrying the waveform in radio.
Wiki User
∙ 9y ago
Wiki User
∙ 13y agoModulation is the process of modifying a carrier wave (the transmitting wave) to carry a message signal. The message could be sound (music, talking), or data (1's and 0's), or a video TV signal for example.
Amplitude Modulation (AM): You tune your radio to 950 kHz. That is the carrier frequency. The radio station takes the message as a signal, and changes the amplitude (strength) of the carrier signal in proportion to how the message signal is changing. This is probably the simplest method as far as electronic circuitry goes.
Frequency Modulation (FM): The actual frequency of the carrier wave is adjusted in proportion to the message signal. So, for example you have your FM radio tuned to 96.1 MHz, the actual signal that you receive could vary between say 96.08 and 96.12 (MHz).
The circuitry of FM is a little more complex than AM, but higher quality is possible. With AM, since the message is encoded as the strength of the signal, any noise or disturbance which changes the strength of the signal (which you receive) will change the message which you receive. So when listening to AM, and you drive under a power line, you can hear the hum. Or a lightning strike gets received by your station as well as a big amplitude signal. With FM, it doesn't matter if the amplitude of the signal suddenly increases, because that's not where the message is encoded.
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List two differences between information signal and carrier signal.?
A: A carrier carry information by modulation either Amplitude or Frequency modulation. Therefore AM and FM RADIO M stand for modulation
Sinusoidal pwm generation using modulation index?
Not sure what type of modulation you are looking for, but there are two that can be manipulated, either individually or in conjunction:Frequency modulation index refers to the relation between the sine wave frequency (sine_freq) and the triangle (or saw-tooth) wave frequency (triang_freq).The frequency modulation index is equal to ((triang_freq)/(sine_freq)).Amplitude modulation index refers to the relation between the sine wave amplitude (sine_amp) and the triangle (or saw-tooth) wave amplitude (triang_amp).The amplitude modulation index is equal to ((sine_amp)/(triang_amp)).Varying the modulation index (normally by varying the frequency or amplitude of the triangle wave form) changes that respective modulation index.From personal experience, an appropriate amplitude modulation index for an SPWM waveform should be around 0.8(that is, if the triangle has an amplitude of 10, the sine would have an amplitude of 8). This index should never be equal to 1 (one); it should always be less. A.K.A.: the triangle-wave amplitude should always be greater than the sine-wave.On the other hand, a triangle-wave frequency much greaterthan the sine-wave frequency makes an SPWM that in turn generates a "cleaner" synthesized sine-wave in the H-bridge you are probably using. Try different freq. modulation indexes, but an index of at least 10 should be used (preferably somewhere around 100 if you want a good SPWM). That is, if the sine-wave frequency is 60 Hz, the triangle-wave frequency should be above 600, preferably 6,000 or more. Complications in the filter design in the "output" of the H-bridge will vary greatly when playing around with the frequency modulation index. That being said, keeping the amplitude modulation index at a static 0.8, and playing around with the triangle-wave frequency should be your best bet.
What is the difference between microwave and an AM signal?
The primary difference is that the microwave signal is of a much higher frequency than an AM signal, if that AM signal is speaking to AM broadcast radio. In general, AM, or amplitude modulation, is not generally used as a modulation technique on microwave frequencies because there are other ways to put a signal on a microwave carrier that allow more information to be transmitted. AM is "low frequency" RF, while FM is a bit higher on the radio frequency spectrum, and microwaves are further on up.
What is difference between pulse width modulation and pulse position modulation?
Frequency modulation, as the name suggests, modulates the carrier by changing the frequency of the signal emitted. Pulse width modulation, changes the on-time of a square wave, but leaves the frequency of the carrier wave unchanged. So, in frequency modulation, the frequency will vary between, say, 80kHz and 120kHz with a constant power level, but in pulse width modulation, the frequency will stay at 100kHz, but the on-time (the length of each pulse) will vary, hence the power level will vary accordingly.
What is the relation between carrier frequency and modulating signal?
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.
What is the difference between am raido and FM radio?
A: AM radio is an Amplitude Modulation transmission . Meaning it has fix frequency but it is modulated by the signal. FM Frequency Modulation the frequency is modulated by the signal
What is the difference between frequency modulation and phase modulation?
The difference between frequency modulation and phase modulation is that with frequency modulation the angular frequency of the signal is modified while with the phase modulation, the phase angle of the signal is modified.
Sound quality between AM and FM?
There are two types of modulations. They are amplitude modulation and frequency modulation. In AM, amplitude of the signal is modified. In FM, frequency is getting modulated. Frequency modulated with carrier waves are transmitted and received by receivers without any distortion.
What is the difference between FM and AM radio waves?
AM means Amplitude(=height) modulation, so the frequency stays the same and the message is coded into variations of the strength of the signal. FM stands for Frequency modulation. Here the strength of the signal stays the same and the message is coded into changes in frequency instead.
What is the difference between am radios waves and FM radio waves?
AM means Amplitude(=height) modulation, so the frequency stays the same and the message is coded into variations of the strength of the signal. FM stands for Frequency modulation. Here the strength of the signal stays the same and the message is coded into changes in frequency instead.
List two differences between information signal and carrier signal.?
A: A carrier carry information by modulation either Amplitude or Frequency modulation. Therefore AM and FM RADIO M stand for modulation
What is the difference between frequency and and amplitude?
so...saying about acoustic waves for e.?amplitude influences loudness and frequency - pitch of tone
Sinusoidal pwm generation using modulation index?
Not sure what type of modulation you are looking for, but there are two that can be manipulated, either individually or in conjunction:Frequency modulation index refers to the relation between the sine wave frequency (sine_freq) and the triangle (or saw-tooth) wave frequency (triang_freq).The frequency modulation index is equal to ((triang_freq)/(sine_freq)).Amplitude modulation index refers to the relation between the sine wave amplitude (sine_amp) and the triangle (or saw-tooth) wave amplitude (triang_amp).The amplitude modulation index is equal to ((sine_amp)/(triang_amp)).Varying the modulation index (normally by varying the frequency or amplitude of the triangle wave form) changes that respective modulation index.From personal experience, an appropriate amplitude modulation index for an SPWM waveform should be around 0.8(that is, if the triangle has an amplitude of 10, the sine would have an amplitude of 8). This index should never be equal to 1 (one); it should always be less. A.K.A.: the triangle-wave amplitude should always be greater than the sine-wave.On the other hand, a triangle-wave frequency much greaterthan the sine-wave frequency makes an SPWM that in turn generates a "cleaner" synthesized sine-wave in the H-bridge you are probably using. Try different freq. modulation indexes, but an index of at least 10 should be used (preferably somewhere around 100 if you want a good SPWM). That is, if the sine-wave frequency is 60 Hz, the triangle-wave frequency should be above 600, preferably 6,000 or more. Complications in the filter design in the "output" of the H-bridge will vary greatly when playing around with the frequency modulation index. That being said, keeping the amplitude modulation index at a static 0.8, and playing around with the triangle-wave frequency should be your best bet.
What is the difference between a sound of low pitch and high pitch amplitude or frequency?
Low frequency = low pitch = long waves
What is the difference between the standard amplitude modulation linear addition and multiplication of signals?
In modulation u r sending two signals but their frequencies are sum or difference of carrier frequency and signal frequency.In addition u send two signals at two different frequencies so more interference.
What has the author John N Morrissey written?
John N. Morrissey has written: 'A comparison between frequency modulation and amplitude modulation for a distance measuring equipment' -- subject(s): Electronics
What is an AM transmitter?
Aplitude ModulationAn AM transmitter is a Amplitude Modulated transmitter where the amplitude of the Radio Frequency signal is modulated, usually used in the lower frequency bands where the frequency is to low for Frequency Modulation (FM), it was the first type of modulation used in radio communication FM was developed in the late 1950's and is not sensitive to static interference as AM AnswerAM is Amplitude Modulation that is the RF signals amplitude is modulated with the audio signal. this modulation is done because the audio signal being of low frequency cannot be transmitted to longer distance so the audio signal is amplitude modulated with RF signal and then transmitted into the air
