|Subject:||[Discuss-gnuradio] Fwd: Correlation Estimator in 3.7.10|
|Date:||Tue, 27 Sep 2016 09:37:06 -0600|
|Alright, after some more thought I believe I understand what is going on.|
By looking at the cross-correlation power for the current input samples, the threshold can be calculated as a desired false alarm rate. An “arbitrary” threshold can be set independently of the received signal power.
Unfortunately, for the test_corr_est.grc example, you just can’t set the threshold high enough to avoid false alarms. I tried the CE block with up to 0.999999 for the threshold and it was still a mess, though much better.
That said, for my own application/flowgraph, setting the CE block threshold to 0.9999 appears to work. I can set as “low” as 0.999, but that’s it.
This makes me wonder why bother to have a threshold parameter at all? Maybe just set the calculated d_pfa value to 10 or something and be done with it. Of course, we all hate magic numbers, and so doing would introduce a second number to the algorithm (the first is a multiplier of 4 in the peak thresholding logic).
Thanks for your patience…
|[Prev in Thread]||Current Thread||[Next in Thread]|