Motivating Undergraduate Communication Theory Using GNU Radio

Abstract

Typical undergraduate communication theory textbooks start from amplitude, frequency, and phase modulation using continuous time signal processing, followed by an introduction to random processes, before digital (and discrete time) communications systems are introduced in the second half of the book. This has led to a drop in enrollment in our undergraduate communications track sequence, largely due to students being overwhelmed with the mathematics of linear systems and probability theory before they have been motivated enough by seeing the applicability of communication theory to the wireless devices that they have come to embrace in their daily lives. We promote a modified approach that uses GNU Radio flowgraphs early in the course to build and analyze a basic digital communication system in parallel with developing the necessary communication theory background. Since GNU Radio is a complex and sophisticated software development toolkit, we place a lot of emphasis on making it a tool that is as transparent and as easy to use as possible by creating carefully designed hierarchical blocks that partition the communication system into subsystems with well defined interfaces and parameter settings.