Howtosignalprocessing
- What is envelope detector in AM?
- Under what condition can envelope detector be used for demodulation of AM signal?
- How do you demodulate an AM signal?
- How do you calculate the envelope of the AM signal?
What is envelope detector in AM?
An envelope detector is an electronic circuit that takes a high-frequency signal as input and provides an output which is the envelope of the original signal. ( ωc » ω m ) It consists of two main elements: Diode / rectifier - serves to pass one half of the received signal over the other.
Under what condition can envelope detector be used for demodulation of AM signal?
An envelope detector can be used to demodulate a previously modulated signal by removing all high frequency components of the signal. The capacitor and resistor form a low-pass filter to filter out the carrier frequency.
How do you demodulate an AM signal?
An AM radio signal can be demodulated by rectifying it to remove one side of the carrier, and then filtering to remove the radio-frequency component, leaving only the modulating audio component. This is equivalent to peak detection with a suitably long time constant.
How do you calculate the envelope of the AM signal?
e(t) = Ac|1 + kam(t)| is called the envelope of the AM signal.
