| Filter Specifications | Contains the following options:
- Cutoff Frequency (Hz)—Specifies the cutoff frequency of the filter. This option is available only when you select Lowpass or Highpass from the Filtering Type pull-down menu. The default is 100.
- Low cutoff frequency (Hz)—Specifies the low cutoff frequency of the filter. This option is available only when you select Bandpass or Bandstop from the Filtering Type pull-down menu. The default is 100.
- High cutoff frequency (Hz)—Specifies the high cutoff frequency of the filter. This option is available only when you select Bandpass or Bandstop from the Filtering Type pull-down menu. The default is 400.
- Finite impulse response (FIR) filter—Creates an FIR filter, which depends only on the current and past inputs. Because the filter does not depend on past outputs, the impulse response decays to zero in a finite amount of time. Because FIR filters return a linear phase response, use FIR filters for applications that require linear phase responses.
- Taps—Specifies the total number of FIR coefficients, which must be greater than zero. The default is 29. This option is available only when you select the Finite impulse response (FIR) filter option. Increasing the value of Taps causes the transition between the passband and the stopband to become steeper. However, as the value of Taps increases, the processing speed becomes slower.
- Infinite impulse response (IIR) filter—Creates an IIR filter, which is a digital filter with impulse responses that can theoretically be infinite in length or duration.
- Topology—Determines the design type of the filter. You can create either a Butterworth, Chebyshev, Inverse Chebyshev, Elliptic, or Bessel filter design. This option is available only when you select the Infinite impulse response (IIR) filter option. The default is Butterworth.
- Order—Order of the IIR filter, which must be greater than zero. This option is available only when you select the Infinite impulse response (IIR) filter option. The default is 3. Increasing the value of Order causes the transition between the passband and the stopband to become steeper. However, as the value of Order increases, the processing speed becomes slower, and the number of distorted points at the start of the signal increases.
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