The Filter Specification screen is used to define the basic configuration and performance of the filter.
- Component Name
- The user-defined filter component instance name.
Filter Coefficients
- Coefficient Source
- Specifies which coefficient input method to use, directly in the GUI using the Coefficient Vector parameter or from a. coe file specified by the Coefficient File parameter.
- Coefficient Vector
- Used to specify the filter coefficients directly in the GUI. The filter coefficients are specified in decimal using a comma delimited list as for the coefdata field in the Filter Coefficient Data file. As with the coe file, the filter coefficients can be specified using non-integer real numbers which the FIR Compiler quantizes appropriately, given your requirements. See Coefficient Quantizationfor more details.
- Coefficients File
- Coefficient file name. This is the file of filter coefficients. The file has a .coe extension, and the file format is described in the See Filter Coefficient Data section. The file can be selected through the dialog box activated by the Browse.
- Show Coefficients
- Show Coefficients: Selecting this button displays the filter coefficient data defined in the specified Coefficient file in a pop-up window.
- Number of Coefficient Sets
- Number of Coefficient Sets: The number of sets of filter coefficients to be implemented. The value specified must divide without remainder into the number of coefficients derived from the coe file or Coefficient Vector.
- Number of Coefficients (per set)
- The number of filter coefficients per filter set. This value is automatically derived from the specified coefficient data and the specified number of coefficient sets.
- Number of Coefficients (per set)
- The number of filter coefficients per filter set. This value is automatically derived from the specified coefficient data and the specified number of coefficient sets.
- Use Reloadable Coefficients
- When the Reloadable option is selected, a coefficient reload interface is provided on the core.
Filter Specification
- Filter Type
- Five filter types are supported: Single-rate FIR, Interpolating FIR, Decimating FIR, Hilbert transform and Interpolated FIR.
- Inferred Coefficient Structure(s)
- Displays the coefficient structures, that can be supported for the selected filter type, detected by the GUI in the specified coefficients. The inferred coefficient structure (the first item in the list) can be overridden using the Coefficient Structure parameter later in the GUI. Supported coefficient structures are: Non-symmetric, Symmetric, Negative Symmetric, Half-band and Hilbert.
The combination of Filter Type, Coefficient Structure and Filter Architecture selects the implementation used by the core.
- Rate Change Type
- This field is applicable to Interpolation and Decimation filter types. Used to specify an Integer or Fixed Fractional rate change.
- Interpolation Rate Value
- This field is applicable to all Interpolation filter types and Decimation filter types for Fractional Rate Change implementations. The value provided in this field defines the up-sampling factor, or P for Fixed Fractional Rate (P/Q) resampling filter implementations.
- Decimation Rate Value
- This field is applicable to the all Decimation and Interpolation filter types for Fractional Rate Change implementations. The value provided in this field defines the down-sampling factor, or Q for Fixed Fractional Rate (P/Q) resampling filter implementations.
- Zero Packing Factor
- This field is applicable to the interpolated filter only. The zero packing factor specifies the number of 0s inserted between the coefficient data specified by you. A zero packing factor of k inserts k-1 zeros between the supplied coefficient values.