PLL-based Pitch Detection and Tracking for Audio Signals

Pitch detection and tracking can be used for several audio effects, such as time and pitch scaling and the generation of harmonic signals related to the detected fundamental frequency. A variety of audio effects has efficiently been implemented by time-domain processing. Pitch tracking of monophonic audio signals can also be performed by time domain techniques. This paper introduces a novel phase lock loop based frequency demodulator for pitch detection and tracking. We will derive the guidelines for parameters of such a kind of pitch tracker and show performance evaluations for a certain type of input signals. The resulting implementation is suited for producing real-time pitch tracking on simple hardware systems with low computational complexity.