Real-time DSP basics using Arduino and the Analog Shield SAR codec board

Abstract

The Arduino micro-controller development platform has received a lot of attention from hobbyist (makers) as well as university engineering programs. The ability to perform simple, yet effective, real-time DSP, is now easily achieved with Arduino and the Analog Shield. The ADC and DAC of the shield allow aliasing and reconstruction issues to be fully explored. Most other audio DSP platforms employ sigma-delta converters, which integrate the ADC anti-aliasing and DAC reconstruction filters into the silicon, hence there is no way to probe the raw signals. We further advocate portable PC-based instrumentation, such as the Analog™Discovery. Programming the Arduino platform is easier than more sophisticated platforms, hence students can focus on key educational issues involving embedded systems, sampling theory, FIR filtering, upsampling and down sampling, and a taste of undersampling sampling as found in software defined radio. Sample investigations show how effective this platform is at revealing DSP math in action.