FilterDesignLab-IIR is a design and simulation environment for digital Infinite Impulse Response (IIR) filters. It is structured into four views for designing the gain, analyzing the phase, simulating test signals, and generating code and filter coefficients.
For a given filter brickwall specification of a digital lowpass, highpass, bandpass, or bandstop, it instantaneously finds the optimal Butterworth, Cheby-I, Cheby-II, or Elliptical filter of lowest order. The phase shift, the group delay and phase delay and the location of the poles and zeros of the transfer function are displayed along with the filter gain. The design and simulation occurs in real-time and is done either by mouse or text input.
The resulting digital filter is instantaneously applied to a test-signal or an imported data set (csv, ascii, txt - format). The test signal resembles either a shifted noisy sine wave, or a step, respectively, delta impulse signal.