When listening to an FM radio station, you tune your receiver to the station's center frequency. Your radio then uses this frequency as a reference to demodulate the audio information carried on the signal, allowing you to hear the content being broadcast.
For example, if a radio station has a center frequency of 92.5 MHz, you would tune your radio to that frequency to listen to their broadcast. The center frequency is the key identifier that allows your radio to lock onto and receive the specific station's signal.
It's important to note that the center frequency is distinct from the modulation frequency. The modulation frequency, often referred to as the "deviation," determines the amount of variation or "swing" in the carrier frequency used to transmit the audio information. In FM broadcasting, the deviation is standardized to be ±75 kHz, which defines the range of frequency variation allowed around the center frequency.
Therefore, the center frequency is the specific frequency assigned to each radio station within the FM band, and it acts as the reference point for tuning in and receiving their broadcasts accurately.