Plateau Detector

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Detects a plateau and marks the middle.

Detect a plateau of a-priori known height. Input is a stream of floats, the output is a stream of bytes. Whenever a plateau is detected, the middle of that plateau is marked with a '1' on the output stream (all other samples are left at zero).

You can use this in a Schmidl & Cox synchronisation algorithm to interpret the output of the normalized correlator. Just pass the length of the cyclic prefix (in samples) as the max_len parameter).

Unlike the peak detectors, you must the now the absolute height of the plateau. Whenever the amplitude exceeds the given threshold, it starts assuming the presence of a plateau.

An implicit hysteresis is provided by the fact that after detecting one plateau, it waits at least max_len samples before the next plateau can be detected.


(R): Run-time adjustable

Max plateau length
Maximum length of the plateau
Threshold (R)
Anything above this value is considered a plateau

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
Header files
Public header files
Block definition