The visible radio: process visualization of a software-defined radio

In this case study, a data-oriented approach is used to visualize a complex digital signal processing pipeline. The pipeline implements a frequency modulated (FM) software-defined radio (SDR). SDR is an emerging technology where portions of the radio hardware, such as filtering and modulation, are replaced by software components. We discuss how an SDR implementation is instrumented to illustrate the processes involved in FM transmission and reception. By using audio-encoded images, we illustrate the processes involved in radio, such as how filters are used to reduce noise, the nature of a carrier wave, and how frequency modulation acts on a signal. The visualization approach used in this work is very effective in demonstrating advanced topics in digital signal processing and is a useful tool for experimenting with the software radio design.