summaryrefslogtreecommitdiff
path: root/gnuradio-core
diff options
context:
space:
mode:
authorTom Rondeau2009-10-12 13:26:00 -0400
committerTom Rondeau2009-10-12 13:26:00 -0400
commitcd963d806b7f324fd845c7b51ef20985000b774c (patch)
tree9f21100ad438364dc2b6e5dc43e5553426febc97 /gnuradio-core
parentb5374350ea98bee6802976937f84ce91f1f721a6 (diff)
downloadgnuradio-cd963d806b7f324fd845c7b51ef20985000b774c.tar.gz
gnuradio-cd963d806b7f324fd845c7b51ef20985000b774c.tar.bz2
gnuradio-cd963d806b7f324fd845c7b51ef20985000b774c.zip
Working DBPSK implementation with new PFB clock recovery block. The feedforward AGC wasn't playing nicely, the frequency aquistion range was increased to swing half the sample rate in either direction, and the number of filter phases to use was increased to 32.
Diffstat (limited to 'gnuradio-core')
-rw-r--r--gnuradio-core/src/python/gnuradio/blks2impl/dbpsk2.py15
1 files changed, 8 insertions, 7 deletions
diff --git a/gnuradio-core/src/python/gnuradio/blks2impl/dbpsk2.py b/gnuradio-core/src/python/gnuradio/blks2impl/dbpsk2.py
index e9e3e965f..e2bce5ff0 100644
--- a/gnuradio-core/src/python/gnuradio/blks2impl/dbpsk2.py
+++ b/gnuradio-core/src/python/gnuradio/blks2impl/dbpsk2.py
@@ -230,12 +230,13 @@ class dbpsk2_demod(gr.hier_block2):
arity = pow(2,self.bits_per_symbol())
# Automatic gain control
- #self.agc = gr.agc2_cc(0.6e-1, 1e-3, 1, 1, 100)
- self.agc = gr.feedforward_agc_cc(16, 1.0)
+ self.agc = gr.agc2_cc(0.6e-1, 1e-3, 1, 1, 100)
+ #self.agc = gr.feedforward_agc_cc(16, 1.0)
self._costas_beta = 0.25 * self._costas_alpha * self._costas_alpha
- fmin = -0.25
- fmax = 0.25
+ # Allow a frequency swing of +/- half of the sample rate
+ fmin = -0.5
+ fmax = 0.5
self.clock_recov = gr.costas_loop_cc(self._costas_alpha,
self._costas_beta,
@@ -247,9 +248,9 @@ class dbpsk2_demod(gr.hier_block2):
self._timing_beta = 0.020
# RRC data filter
- nfilts = 8
+ nfilts = 32
ntaps = 11 * samples_per_symbol*nfilts
- taps = gr.firdes.root_raised_cosine(nfilts, nfilts, 0.25, self._excess_bw, ntaps)
+ taps = gr.firdes.root_raised_cosine(nfilts, nfilts, 1.0/float(self._samples_per_symbol), self._excess_bw, ntaps)
self.time_recov = gr.pfb_clock_sync_ccf(self._samples_per_symbol,
self._timing_alpha,
taps, nfilts, nfilts/2, self._timing_max_dev)
@@ -279,7 +280,7 @@ class dbpsk2_demod(gr.hier_block2):
# Connect and Initialize base class
self.connect(self, self.agc,
- #self.clock_recov,
+ self.clock_recov,
self.time_recov,
self.diffdec, self.slicer, self.symbol_mapper, self.unpack, self)