How does the Ratio Detector recover the intelligence from the FM envelope?

The Ratio Detector recovers intelligence from the FM envelope by comparing the amplitudes of two signals derived from the FM waveform. It utilizes a phase-locked loop to demodulate the frequency variations, effectively translating frequency changes into amplitude changes. By taking the ratio of these amplitudes, the detector can extract the original modulation signal, allowing for effective demodulation of the frequency-modulated signal. This method is particularly effective in reducing the effects of noise and improving the clarity of the recovered audio.