A step toward real-time interactive FIR filter design

This paper outlines the development of a new tool for the digital signal processing engineer. The coupling of a frequency sampling technique for the design of linear-phase FIR filters with recent advances in digital signal processors has led to the development of a real-time interactive FIR filter design technique. The system accepts samples of the desired frequency response as inputs, determines the corresponding linear-phase FIR filter, and implements the filter. This allows the DSP engineer to adjust the filter while simultaneously examining its response to an input signal. The input signal might be a test signal derived from a spectrum analyzer, an audio signal, or any general signal source of interest. This flexibility provides the user with what will hopefully be a valuable tool in a broad variety of digital signal processing applications. The simplicity and utility of the system is further emphasized by the implementation of the system on a single Texas Instruments TMS32010 digital signal processor.