FMdemodulaatioon

FM demodulation is a process used to extract the original audio signal from a frequency-modulated (FM) signal. This technique is commonly employed in radio communications, particularly in FM broadcasting, to ensure high-quality audio transmission. FM demodulation involves several key steps:

First, the received FM signal is amplified to an appropriate level for processing. This amplified signal is then passed through a limiter, which ensures that the amplitude of the signal remains constant, regardless of the strength of the received signal. This step is crucial because FM demodulation is sensitive to amplitude variations.

Next, the limited signal is fed into a frequency discriminator. This component extracts the frequency variations from the FM signal, converting them back into the original audio signal. The frequency discriminator works by comparing the phase of the incoming signal to a reference signal, generating an output voltage proportional to the frequency deviation.

The output from the frequency discriminator is then passed through a low-pass filter to remove any high-frequency components that may have been introduced during the demodulation process. This filtered signal is the demodulated audio signal, which can be amplified and played through a speaker or other audio device.

FM demodulation is preferred in many applications due to its ability to provide high-quality audio and its resistance to noise and interference. However, it requires more complex circuitry and processing compared to amplitude modulation (AM) demodulation. Despite this, FM demodulation remains a widely used technique in modern communication systems.