Peak Detector2: Difference between revisions

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Detect the peak of a signal.
Detect the peak of a signal.


If a peak is detected, this block outputs a 1, else it outputs 0's.
If a peak is detected, this block outputs a 1, else it outputs 0's. A separate debug output may be connected, to view the internal estimated mean described below.


== Parameters ==
== Parameters ==
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; TH factor rise (''R'')
; TH factor rise (''R'')
: Determines when a peak has started. An average of the signal is calculated and when the value of the signal goes over threshold_factor_rise*average, we start looking for a peak.
: Determines when a peak is present. An average of the input signal is calculated (through a single-pole autoregressive filter) and when the value of the input signal goes over threshold_factor_rise*average, we assume we are in the neighborhood of a peak. The block will then find the position of the maximum within a window of look_ahead samples starting at the point where the threshold was crossed upwards.
 
; TH factor fall (''R'')
: Determines when a peak has ended. An average of the signal is calculated and when the value of the signal goes below threshold_factor_fall*average, we stop looking for a peak.


; Look ahead (''R'')
; Look ahead (''R'')
: Used when the threshold is found to look if there another peak within this step range. If there is a larger value, we set that as the peak and look ahead again. This is continued until the highest point is found with this look-ahead range.
: Used when the threshold is found to look if there another peak within this step range.


; Alpha (''R'')
; Alpha (''R'')
: The gain value of a moving average filter
: One minus the pole of a single-pole autoregressive filter that evaluates the average of the input signal.


== Example Flowgraph ==
== Example Flowgraph ==

Revision as of 15:23, 23 August 2019

Detect the peak of a signal.

If a peak is detected, this block outputs a 1, else it outputs 0's. A separate debug output may be connected, to view the internal estimated mean described below.

Parameters

(R): Run-time adjustable

TH factor rise (R)
Determines when a peak is present. An average of the input signal is calculated (through a single-pole autoregressive filter) and when the value of the input signal goes over threshold_factor_rise*average, we assume we are in the neighborhood of a peak. The block will then find the position of the maximum within a window of look_ahead samples starting at the point where the threshold was crossed upwards.
Look ahead (R)
Used when the threshold is found to look if there another peak within this step range.
Alpha (R)
One minus the pole of a single-pole autoregressive filter that evaluates the average of the input signal.

Example Flowgraph

Insert description of flowgraph here, then show a screenshot of the flowgraph and the output if there is an interesting GUI. Currently we have no standard method of uploading the actual flowgraph to the wiki or git repo, unfortunately. The plan is to have an example flowgraph showing how the block might be used, for every block, and the flowgraphs will live in the git repo.

Source Files

C++ files
TODO
Header files
TODO
Public header files
TODO
Block definition
TODO