An Acoustooptic FM Receiver Demonstrating Some Principles of Modern Signal Processing

An acoustooptic FM receiver can be constructed by using a Bragg sound cell plus some simple optics and electronics. This application has significant pedagogical value because, in spite of the simplicity of implementation, it demonstrates a wide variety of physical and electrical principles applicable to modern signal processing. In this paper, we include a tutorial on the principles of acoustooptics which provides a background sufficient for the understanding of the Bragg cell FM receiver described in the text. The FM receiver we have built has a frequency resolution of 200 kHz, enough to separate FM stations. A general guideline for controlling this resolution will also be discussed. The project has been used as a demonstration for senior-level undergraduate students in an electrical engineering design class.