Frequency-Locked Loop Also Known as Automatic Frequency Control (AFC) Loop
The Frequency-Locked Loop (FLL), also referred to as an Automatic Frequency Control (AFC) loop, employs a feedback mechanism to adjust input frequency variations, ultimately achieving precise frequency tracking. Widely used in radar and satellite navigation systems for Doppler frequency tracking, FLL implementations typically involve phase detectors, loop filters, and voltage-controlled oscillators (VCOs) in their signal processing chains.