State the process FM detection? State it‟s any two types.

1 Answer

FM detection: In any radio that is designed to receive frequency modulated signals there is some form of FM demodulator or detector. This circuit takes in frequency modulated RF signals and takes the modulation from the signal to output only the modulation that had been applied at the transmitter. In order to be able to demodulate FM it is necessary for the radio receiver to convert the frequency variations into voltage variations. It is necessary to have a response that is as linear as possible over the required bandwidth. The response that is normally seen for an FM demodulator / FM detector is known as an "S" curve for obvious reasons. There is a linear portion at the centre of the response curve and towards the edge the response becomes very distorted.

The different types of FM Detectors are:

1. Simple Slope Detector

2. Balanced Slope Detector

3. Ratio Detector

4. Phase Discriminator

5. FM Detector using Phase Locked Loop (PLL)
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