From afe88fcf45157037a0283b00f38fef45b0c350f0 Mon Sep 17 00:00:00 2001
From: Manuel Pitz <manuel.pitz@eonerc.rwth-aachen.de>
Date: Wed, 16 Jun 2021 14:00:52 +0000
Subject: [PATCH] first version of prabolic freq estimation
---
lib/hooks/dft.cpp | 51 +++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 51 insertions(+)
diff --git a/lib/hooks/dft.cpp b/lib/hooks/dft.cpp
index 08dde4586..82a052835 100644
--- a/lib/hooks/dft.cpp
+++ b/lib/hooks/dft.cpp
@@ -779,6 +779,15 @@ public:
{
assert(state == State::PARSED);
+ if (!freqEstimateTypeC) {
+ logger->info("No Frequency estimation type given, assume no none");
+ freqEstType = FreqEstimationType::NONE;
+ }
+ else if (strcmp(freqEstimateTypeC, "quadratic") == 0)
+ freqEstType = FreqEstimationType::QUADRATIC;
+
+
+
if (endFreqency < 0 || endFreqency > sampleRate)
throw RuntimeError("End frequency must be smaller than sampleRate {}", sampleRate);
@@ -1142,6 +1151,48 @@ static HookPlugin<DftHook, n, d, (int) Hook::Flags::NODE_READ | (int) Hook::Flag
return { y_Fmax, i };
}
+
+
+ /**
+ * This function is calculating the mximum based on a quadratic interpolation
+ *
+ * This function is based on the following paper:
+ * https://mgasior.web.cern.ch/pap/biw2004.pdf
+ *
+ * In particular equation 10
+ *
+ */
+ Point quadraticEstimation(double x1, double x2, double x3, double y1, double y2, double y3, unsigned maxFBin)
+ {
+
+ //double y_max = x2 - (y3 - y1) / (2 * ( 2 * y2 - y1 - y3));
+ double y_Fmax = 0;
+
+ /*Quadratic Method */
+ double maxBinEst = ((y3 - y1) / ( 2 * ( 2 * y2 - y1 - y3)));
+
+
+
+ logger->info("y3 - y1 {} ; y_max : {}", (y3 - y1), maxBinEst);
+
+ maxBinEst = (double)maxFBin + maxBinEst;
+
+ /*Jain’s Method
+ if (y1 > y3)
+ {
+ y_max = (double)maxFBin - 1 + (((y2 / y1) / ( 1 + (y2/y1))));
+ }
+ else
+ {
+ y_max = (double)maxFBin + ((y3 / y2) / ( 1 + (y3 / y2)));
+ }*/
+
+ y_Fmax = startFreqency + maxBinEst * frequencyResolution;
+
+ Point ret = {y_Fmax, 0};
+
+ return ret;
+ }
};
/* Register hook */