A Phase Locked Loop is a feedback system combining a voltage controlled oscillator and a phase comparator so connected that the oscillator maintains a constant phase angle relative to a reference signal. The oscillator generates a periodic signal and the phase detector compares the phase of the input signal with the phase of the oscillator’s signal, and adjusts the oscillator to keep the phases matched. Keeping the input and output phase in lock means keeping the input and output frequencies the same. PLLs are used in almost every telecommunication electronic devices. In radio transmitters PLL is used to synthesize new frequencies which are multiple of a reference frequency, with the same stability as the reference frequency. They are widely used for synchronization purposes. PLL can be used for recovering a small signal from noisy communication channels and for demodulation of both AM and FM signals. The goal of my project was to do researches about PLL based frequency synthesis.
Sukta Beáta, hallgató, Budapest University of Technology and Economics, Faculty of Electrical Engineering and Informatics
2015.02.24.
A kutatási beszámoló letölthető innen (PDF)