Detection of FM Waves

Frequency Modulation (FM) waves can be detected using several different methods, including:

1. Slope Detector: In this method, the FM signal is passed through a bandpass filter to remove any unwanted frequencies. The filtered signal is then passed through a diode or transistor circuit that generates a voltage proportional to the rate of change of the FM signal frequency. This voltage is then filtered to recover the original modulating signal.

2. Balanced Discriminator: In this method, the FM signal is passed through a balanced frequency discriminator that generates an output voltage proportional to the frequency deviation of the FM signal. The output voltage is then filtered to recover the modulating signal.

3. Phase-Locked Loop (PLL) Detector: In this method, the FM signal is used to control the frequency of a PLL circuit, which generates an output voltage proportional to the phase difference between the input FM signal and the output of the PLL. The output voltage is then filtered to recover the modulating signal.

4. Quadrature Detector: In this method, the FM signal is mixed with a reference signal that is 90 degrees out of phase with the original FM signal. The resulting signal is passed through a low-pass filter to recover the modulating signal.

Overall, the choice of FM detection method depends on factors such as the desired frequency range, modulation depth, and accuracy, as well as the available hardware and circuitry.