DAPL – DSP Filtering Commands

DAPL provides some classic DSP filtering methods, using pre-defined or custom-designed filters.

These filters can operate on any data type. Typical applications include smoothing, noise reduction, and detection of frequencies in selected bands.

Applications requiring traditional types of IIR (infinite impulse response) lowpass filters can apply the easy-to-use digital equivalents from the DAPL IFM command module.

BUTTERWORTH

General purpose filter, with gentle compromises in passband, stopband, and phase delay.

BESSEL

Filter emphasizing uniform group delay with slower rolloff than BUTTERWORTH.

CHEBYSHEV

Filter achieving fast stopband rolloff at the expense of bounded deviations in passband magnitude and phase.

CHEBYINV

Filter achieving accurately bounded stopband rejection at the expense of magnitude and phase deviations in the passband.

ELLIPTIC

Filter achieving accurate band discrimination at the expense of controlled magnitude deviations and large phase deviations.

Applications that need the most accurate filtering with zero phase distortion can use FIR (finite impulse response) filters.

FIRFILTER

General purpose FIR filtering, for arbitrary designs. Fully compatible with filters developed interactively using DAPstudio.

FIRLOWPASS

High accuracy, pre-designed lowpass filters for oversampling and decimation applications. Decimation factors from 2 to 12.

RAVERAGE

An efficient running average "boxcar" filter useful for removing random noise.

Visit our DSP section for information on applications and techniques.