ScopeFIR is a comprehensive tool for Finite Impulse Response (FIR) filter design. It can:

• Design multi-band complex FIR filters by:
  1. The Parks-McClellan Linear Phase FIR filter design algorithm. Filters may be Lowpass, Bandpass, Highpass, Hilbert, or Differentiator. You may enter band edge frequency into the Filter Specification Editors in terms of the sample rate, and enter band response specifications in your choice of linear or dB units.
  2. The windowing method. First, fill the filter with cosine/sine coefficients using the built-in sine generator function. This sets the center frequency. Next, window the coefficients using one of ScopeFIR's built-in data windows which include Blackman-Harris, Kaiser-Bessel (with choice of Alpha), Hamming, Hanning, and Gaussian. The response shape is set by the window type and the number of filter taps.
  3. Filling the taps with a constant. This creates a "comb" filter.
• View the FIR filters by:
  1. Examining the actual band ripple and attenuation values in the Filter Specification Editors.
  2. Plotting the Frequency Response. ScopeFIR can plot Inphase Magnitude, Quadrature Magnitude, Complex Magnitude, and Complex Phase.
  3. Plotting the Impulse Response. ScopeFIR can plot Inphase, Quadrature, or Complex Impulse Responses.
  4. Viewing the coefficients in the Coefficient Editor. (Professional Edition only.) ScopeFIR lets you view the Inphase and/or Quadrature coefficients in decimal, binary or hex formats.
• Alter the FIR filters by:
  1. Scaling. Changes the gain of the filter. The coefficients can be automatically scaled to create a given gain at a given frequency, or can be automatically scaled to a given maximum coefficient magnitude.
  2. Quantizing. Coefficients can be quantized to N bits.
  3. Mixing. The mixing function mixes the coefficients of an existing filter with a complex sine of a given frequency. This creates a new Complex filter whose response is the same as the original but shifted by the mixing frequency.
  4. Editing. ScopeFIR's Coefficient Editor is a built-in text editor which allows you to edit the filter coefficients. Coefficients can be edited manually, or can copied/pasted to/from the Windows clipboard.
• Import and Export Real or Complex FIR filter coefficient files in many data file formats for use by other applications.
• Of course, ScopeFIR also includes many graphical user interface goodies to make your life in DSP a little easier.