DSP education by fixed-point implementation & measurement

Abstract

Analysis and design of a digital filter, implemented with fixed-point arithmetic, provides students with opportunities to apply and integrate a large variety of concepts. They also learn about various applications and trade-offs. Evaluating the performance of the resulting nonlinear system against the desired response presents interesting choices regarding the utility of various discrete-time measurement approaches. As digital filters are often subsystems in an analog processing chain, it makes sense to measure digital filter performance using analog domain measurements. Measuring performance in real time brings out timing issues not encountered in the discrete-time performance measurements. The re-development of a useful framework for the implementation of such a design experience, using a modern USB-interfaced processor, has provided the additional learning experience that assembly language programming still has its place.