Understanding of the Coherent Demodulation with Phase-Locked Loop

Abstract

The phase-locked loop (PLL) technology is a very important technology in the communication field. With the development of electronic technology toward digitalization, the phase-locked processing of signal needs to be realized in digital way. Therefore, more and more attentions have been paid to the research and application of all digital phase-locked loops. This paper serves as an introduction about the basic background of PLL, the basic characteristics and structure of PLL, and the basic principles of modulation and demodulation. It provides a concise application about the basic principle and main design process of modulation and demodulation of FSK signal, which are realized by using phase-locked loop chip NE564.