User Reference:IIRBandpass: Difference between revisions

Revision as of 11:25, 4 January 2023

Synopsis

Design an IIR filter consisting of up to three parts (high-pass, low-pass and notch) and apply it as part of the signal-processing chain. To use it as a bandpass, specify the desired lower end of the band as a high-pass corner, and the desired upper end of the band as a low-pass corner.

Authors

Jeremy Hill

Parameters

HighPassCorner

High-pass cutoff frequency. The default is 0, which disables the high-pass.

HighPassOrder

Filter order for the high-pass. The default is 2. A value of 0 disables the high-pass.

LowPassCorner

Low-pass cutoff frequency. The default is 0, which disables the low-pass.

LowPassOrder

Filter order for the low-pass. The default is 4. A value of 0 disables the high-pass.

NotchCenter

Notch center frequency. The default is 0, which disables the notch filter.

NotchOrder

Filter order for the notch. The default is 4. A value of 0 disables the notch filter.

Downsample

If LowPassCorner is set, downsample to a sampling rate of 4*LowPassCorner provided that is smaller than the current sampling rate.

The default is 1 (do downsampling).

Rectification

If set to 1, negative values will be replaced with zeros (Half-Wave). If set to 2, negative values will be replaced with their absolute values (Full-Wave). Set to 0 to disable rectification. Note that rectification is done after bandpass filtering, so another low pass filter is likely required to obtain an amplitude estimate.

States

None.

@@ Line 36: / Line 36: @@
 The default is 1 (do downsampling).
+===Rectification===
+If set to 1, negative values will be replaced with zeros (Half-Wave). If set to 2, negative values will be replaced with their absolute values (Full-Wave). Set to 0 to disable rectification. Note that rectification is done ''after'' bandpass filtering, so another low pass filter is likely required to obtain an amplitude estimate.
 ==States==