An AM signal with fM= 3 kHz, and carrier frequency fC= 120 kHz is to be detected by a linear envelope detector.How would we design the low-pass and high pass filter of the detector such that we get an undistorted waveform of the modulating signal from the output.
that is the question asked.
By a linear envelope detector (which is demodulating)we can remove the carrier-signal from the intelligence signal.
In the low pass filter, the capacitor would remove the high frequency. And diode in the filter will add distortion the signal.

 

An envelope detector works with an AM signal. The carrier is 120kHz and the modulatuion is 3kHz. The rectifier and its filter capacitor converts the RF to the modulation signal.

 

An envelope detector works with an AM signal. The carrier is 120kHz and the modulatuion is 3kHz. The rectifier and its filter capacitor converts the RF to the modulation signal.

so how wud we design the low and high pass filter...with including the diode and the capacitor..so we wud get undistorted and modulated signal in the output