Correlation Estimator: Difference between revisions
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; Threshold (''R'') | ; Threshold (''R'') | ||
: Threshold of correlator, | : Threshold of correlator: The meaning of this parameter depends on the threshold method used. For DYNAMIC threshold method, this parameter is actually 1 - Probability of False Alarm (under some inaccurate assumptions). The code performs the check |r[k]|^2 + |r[k+1]|^2 <> -log(1-threshold)*2*E, where r[k] is the correlated incoming signal, and E is the average sample energy of the correlated signal. For ABSOLUTE threshold method, this parameter sets the threshold to a fraction of the maximum squared autocorrelation. The code performs the check |r[k]|^2 <> threshold * R^2, where R is the precomputed max autocorrelation of the given sync word. Default is 0.9. | ||
; Threshold Method | ; Threshold Method | ||
: Method for computing threshold. | : Method for computing threshold. Options: [Absolute, Dynamic] | ||
== Example Flowgraph == | == Example Flowgraph == | ||
This flowgraph is extracted from [https://github.com/gnuradio/gnuradio/blob/master/gr-digital/examples/demod/test_corr_est.grc] | |||
[[File:Test_corr_est_fg.png|800px]] | |||
== Example Output == | |||
[[File:Test_corr_est_out.png|800px]] | |||
== Source Files == | == Source Files == | ||
| Line 36: | Line 42: | ||
; Block definition | ; Block definition | ||
: [https://github.com/gnuradio/gnuradio | : [https://github.com/gnuradio/gnuradio/blob/master/gr-digital/grc/digital_corr_est_cc.block.yml] | ||
Revision as of 03:27, 7 March 2021
Correlates the input signal against the provided vector of samples and outputs a phase and symbol timing estimate.
Parameters
(R): Run-time adjustable
- Symbols
- Set of symbols to correlate against (e.g., a sync word).
- Samples per Symbol
- Samples per symbol
- Tag Marking Delay (R)
- Tag marking delay in samples after the corr_start tag
- Threshold (R)
- Threshold of correlator: The meaning of this parameter depends on the threshold method used. For DYNAMIC threshold method, this parameter is actually 1 - Probability of False Alarm (under some inaccurate assumptions). The code performs the check |r[k]|^2 + |r[k+1]|^2 <> -log(1-threshold)*2*E, where r[k] is the correlated incoming signal, and E is the average sample energy of the correlated signal. For ABSOLUTE threshold method, this parameter sets the threshold to a fraction of the maximum squared autocorrelation. The code performs the check |r[k]|^2 <> threshold * R^2, where R is the precomputed max autocorrelation of the given sync word. Default is 0.9.
- Threshold Method
- Method for computing threshold. Options: [Absolute, Dynamic]
Example Flowgraph
This flowgraph is extracted from [1]
Example Output
Source Files
- C++ files
- TODO
- Header files
- TODO
- Public header files
- TODO
- Block definition
- [2]