Seeq Knowledge Base

Signal Smoothing

The Signal Smoothing tool can be used to reduce high frequency noise from signals using one of five different filters: Seeq Agile, Savitzky-Golay (SG), Low Pass, Moving Average or Exponential.

 Using the Signal Smoothing Tool

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Select the signal to search:  From the dropdown menu select a signal from the details pane, pinned items or recently used sections.

Specify the filter type: Choose to filter using the Seeq Agile Filter, Savitzky-Golay (SG) Filter, Low Pass Filter, Moving Average Filter or Exponential Filter.

Specify the smoothing window: The length of the input signal that the filter can 'see' during its computation. Default = 33 times the period; must be between 3 and 101 times the period, inclusive. (Note: this field is not used in the exponential filter).

Exponential Filter Only

Specify the filter parameter: Choose to filter with a time constant (tau, i.e. 2min) or smoothing factor (alpha, i.e. 0.9). Alpha must be between 0 and 1.


Advanced Options

SG Filter Only

Specify the polynomial factor: The order of the polynomial that will be used to fit each output sample; higher orders will fit the input data more tightly. Defaults to 2; value must be less than the number of periods in the specified window size and between 1 and 7, inclusive. An order of 1 causes this filter to behave similarly to a moving average filter.

Low Pass Filter Only

Specify the cutoff: The filter threshold; frequencies above (or wave periods below) this threshold are filtered, while frequencies below (or periods above) are not filtered. Enter a time period (e.g. 10min) or frequency (e.g. 0.001667Hz).

Specify the sampling rate: The spacing between samples output by this filter. If you don’t specify this value, Seeq will calculate it automatically based on the signal you select.