Which of the following demodulates an RF modulated wave?
Which of the following demodulates an RF modulated wave? Correct Answer Detector
A detector circuit is used to demodulate an RF modulated wave.
There are a number of techniques that can be used to demodulate RF modulated wave depending upon the cost and the nature of the application.
Envelop Detector:
It consists of a diode followed by an RC circuit, which is a simple low-pass filter as shown:
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- During the positive half-cycle of the input signal, the diode conducts and the capacitor charges up to the peak value of the input signal.
- When the input falls below the voltage on the capacitor, the diode becomes reverse-biased and the input disconnects form the output.
- During this period, the capacitor discharges slowly through resistor R.
- On the next cycle of the carrier, the diode again conducts when the input signal exceeds the voltage across the capacitor.
Synchronous/Coherent Detector:
It consists of a linear multiplier (Product modulator) followed by a low pass filter as shown:
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