From: Josh Blum <josh@joshknows.com>
Date: Tue, 1 Sep 2009 01:18:22 +0000 (-0700)
Subject: Modified log power fft block so ref scale is peak to peak.
X-Git-Url: https://git.gag.com/?a=commitdiff_plain;h=0c68c486ec09da471c27b6f4d658ae0ba8f861b7;p=debian%2Fgnuradio

Modified log power fft block so ref scale is peak to peak.
Tweaked fft sink autoscale routine to come up with better numbers.
Modified scope sink ac couple block to use constant tap.
The previous tap calculation would cause failure for very small sample rates.
---

diff --git a/gnuradio-core/src/python/gnuradio/blks2impl/logpwrfft.py b/gnuradio-core/src/python/gnuradio/blks2impl/logpwrfft.py
index cf8eb1be..7ef40be4 100644
--- a/gnuradio-core/src/python/gnuradio/blks2impl/logpwrfft.py
+++ b/gnuradio-core/src/python/gnuradio/blks2impl/logpwrfft.py
@@ -55,9 +55,9 @@ class _logpwrfft_base(gr.hier_block2):
         c2mag = gr.complex_to_mag(fft_size)
         self._avg = gr.single_pole_iir_filter_ff(1.0, fft_size)
         self._log = gr.nlog10_ff(20, fft_size,
-                                 -10*math.log10(fft_size)              # Adjust for number of bins
+                                 -20*math.log10(fft_size)              # Adjust for number of bins
                                  -10*math.log10(window_power/fft_size) # Adjust for windowing loss
-                                 -20*math.log10(ref_scale/2))          # Adjust for reference scale
+                                 -20*math.log10(ref_scale/2)+3.0)      # Adjust for reference scale
         self.connect(self, self._sd, fft, c2mag, self._avg, self._log, self)
 
         self._average = average
diff --git a/gr-wxgui/src/python/fft_window.py b/gr-wxgui/src/python/fft_window.py
index 0529e6a5..4c575f1a 100644
--- a/gr-wxgui/src/python/fft_window.py
+++ b/gr-wxgui/src/python/fft_window.py
@@ -256,15 +256,19 @@ class fft_window(wx.Panel, pubsub.pubsub):
 		if not len(self.samples): return
 		#get the peak level (max of the samples)
 		peak_level = numpy.max(self.samples)
-		#get the noise floor (averge the smallest samples)
-		noise_floor = numpy.average(numpy.sort(self.samples)[:len(self.samples)/4])
-		#padding
-		noise_floor -= abs(noise_floor)*.5
-		peak_level += abs(peak_level)*.1
-		#set the reference level to a multiple of y divs
-		self[REF_LEVEL_KEY] = self[Y_DIVS_KEY]*math.ceil(peak_level/self[Y_DIVS_KEY])
+		#separate noise samples
+		noise_samps = numpy.sort(self.samples)[:len(self.samples)/2]
+		#get the noise floor
+		noise_floor = numpy.average(noise_samps)
+		#get the noise deviation
+		noise_dev = numpy.std(noise_samps)
+		#determine the maximum and minimum levels
+		max_level = peak_level
+		min_level = noise_floor - abs(2*noise_dev)
 		#set the range to a clean number of the dynamic range
-		self[Y_PER_DIV_KEY] = common.get_clean_num((peak_level - noise_floor)/self[Y_DIVS_KEY])
+		self[Y_PER_DIV_KEY] = common.get_clean_num(1+(max_level - min_level)/self[Y_DIVS_KEY])
+		#set the reference level to a multiple of y per div
+		self[REF_LEVEL_KEY] = self[Y_PER_DIV_KEY]*round(.5+max_level/self[Y_PER_DIV_KEY])
 
 	def _reset_peak_vals(self, *args): self.peak_vals = EMPTY_TRACE
 
diff --git a/gr-wxgui/src/python/scopesink_gl.py b/gr-wxgui/src/python/scopesink_gl.py
index b4ae0f33..a5e3ca3c 100644
--- a/gr-wxgui/src/python/scopesink_gl.py
+++ b/gr-wxgui/src/python/scopesink_gl.py
@@ -50,7 +50,7 @@ class ac_couple_block(gr.hier_block2):
 		self.connect(self, lpf, mute, (sub, 1))
 		#subscribe
 		controller.subscribe(ac_couple_key, lambda x: mute.set_mute(not x))
-		controller.subscribe(sample_rate_key, lambda x: lpf.set_taps(2.0/x))
+		controller.subscribe(sample_rate_key, lambda x: lpf.set_taps(0.05))
 		#initialize
 		controller[ac_couple_key] = ac_couple
 		controller[sample_rate_key] = controller[sample_rate_key]