One method to extract the intelligence (signal) from a high frequency carrier in FM receivers is with a phase locked loop.
The carrier frequency will cause interference with any AM station on or near that frequency.
Frequency Modulation must have a carrier whereby the frequency can be modulated by the signal
The frequency with which the carrier frequency is deviated is exactly the modulating frequency, i.e. the frequency of the sound that makes up the music or voice announcement, stereo pilot, SCA subcarrier, etc.
The carrier wave carries the information that you hear. It is modulated by the sound which varies its amplitude or frequency. Without the carrier there would be nothing to vary so you would hear nothing.
because demodulated FM is an audio signal, which the frequency is much smaller that is why it can be transmitted alone. It need carrier which has large frequency. Modulated signal is an audio signal + carrier that is why the amplitude is higher.
Following are the 3 parameter by which high Frequency carrier can be varied by low frequency intelligence signal 1) Amplitude 2) Phase 3) Frequency
frequency of the carrier is varied in accordance to the message signal in FM. Fm receivers are less complex. in Fm lower frequencies produce variation to the modulation index. phase of the carrier is varied in accordance to the message signal in PM. Pm receivers require proper synchronization so it is complex. Modulation index is independent of audio frequency
to shift the frequency of information signal ,at the frequency domain to a higher frequency ...so the information can be transmitted to the receiver.
If you subtract from the carrier frequency the frequency of the tone that modulates it, then filter out the carrier frequency, then you have a lower sideband frequency. If you add to the carrier frequency, filter out the carrier, then you have an upper sideband frequency.
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.
The process of separating the original information or SIGNAL from the MODULATED CARRIER. In the case of AMPLITUDE or FREQUENCY MODULATION it involves a device, called a demodulator or detector, which produces a signal corresponding to the instantaneous changes in amplitude or frequency, respectively. This signal corresponds to the original modulating signal
in frequency modulation, frequency of carrier signal changes. so frequency variations of carrier convey all the information in frequency modulation.
Explain the need for carrier frequency stability in radio transmitters?
Carrier signal is of high frequencies, it gives strength to the original signal because original signal cannot travel long distances so it needs to be strengthen a bit for transmitting. The carrier signal is a high frequency signal, called an RF. Radio Frequency signal, it is to high for the human or animal ear to detect it, so its outside the audible spectrum and can easily be transmitted over the air to receivers that is tuned to receive that frequency and detect any modulation on that signal.
probably (the carrier frequency +- the maximum frequency of the pulse train)/(the carrier frequency) but pulses have a lot of harmonics
Upper sideband = Carrier frequency + modulating frequencyLower sideband = Carrier frequency - modulating frequency
If the intelligence signal striking a microphone was doubled in frequency from 1 kHz to 2 kHz with constant amplitude, (fc) would change from 1 kHz to 2 kHz. Because the intelligence amplitude was not changed, however, the amount of frequency deviation above and below fc will remain the same. On the other hand, if the 1 kHz intelligence frequency were kept the same but its amplitude were doubled, the rate of deviation above and below fc would remain at 1 kHz, but the amount of frequency deviation would double.