Electrical and Computer Engineering Department Main MenuBradley University Main Web Site for Prospective Students for Current Students for Our Alumni for Faculty Contact Information Faculty Directory Senior Projects Labs and Research Areas Useful links ECE Department Home Page Senior Projects


Hybrid Phase-Locked Loop for FM Demodulation
Mike Casina and Sarboland Sadiq

A method of demodulating an FM signal with a hybrid phase-locked loop is presented. In contrast to conventional phase-locked loops, the circuitry is for the most part digital, rather than analog. Advantages, such as stability and absence of adjustments, make a digital or hybrid phase-locked loop more suitable for use in large systems which require microminiaturization. 

A function generator integrated circuit supplies a frequency modulated signal to the phase detector, which consists of a double balanced mixer and a low pass filter. This low pass filter serves to eliminate the high frequency components of this signal. A software program then performs an A/D conversion which translates an analog signal into a series of 8-bit binary data. The superimposed AC components are then filtered out by a software representation of a digital filter. In addition, software programming is then used to implement a digital synthesizer, operating at a fixed clock rate to sample the synchronized signal at different sampling instants. 

[an error occurred while processing this directive]
[Prospective Students] [Current Students] [Alumni] [Faculty]
[Home] [Contact us] [Curriculum] [Senior Projects] [Research] [People] [Links]
Copyright (c)1995-2013 Bradley University. All rights reserved.
. .