diff options
Diffstat (limited to 'gnuradio-core')
-rw-r--r-- | gnuradio-core/src/python/gnuradio/blksimpl/dqpsk.py | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/gnuradio-core/src/python/gnuradio/blksimpl/dqpsk.py b/gnuradio-core/src/python/gnuradio/blksimpl/dqpsk.py index 9459f4243..0563840ff 100644 --- a/gnuradio-core/src/python/gnuradio/blksimpl/dqpsk.py +++ b/gnuradio-core/src/python/gnuradio/blksimpl/dqpsk.py @@ -239,13 +239,13 @@ class dqpsk_demod(gr.hier_block): # Costas loop (carrier tracking) if self._costas_alpha is None: # If no alpha value was specified by the user - alpha_dir = {2:0.075, 3:0.075, 4:0.105, 5:0.105, 6:0.125, 7:0.130} + alpha_dir = {2:0.075, 3:0.09, 4:0.09, 5:0.095, 6:0.10, 7:0.105} self._costas_alpha = alpha_dir[self._samples_per_symbol] costas_order = 4 - # The value of beta is now set to be overdamped; this value can have a huge impact on the + # The value of beta is now set to be underdamped; this value can have a huge impact on the # performance of QPSK. Set to 0.25 for critically damped or higher for underdamped responses. - beta = .15 * self._costas_alpha * self._costas_alpha + beta = .5 0 * self._costas_alpha * self._costas_alpha self.costas_loop = gr.costas_loop_cc(self._costas_alpha, beta, 0.02, -0.02, costas_order) # RRC data filter |