diff options
| author | eb <eb@221aa14e-8319-0410-a670-987f0aec2ac5> | 2006-09-27 05:14:03 +0000 |
|---|---|---|
| committer | eb <eb@221aa14e-8319-0410-a670-987f0aec2ac5> | 2006-09-27 05:14:03 +0000 |
| commit | f1c41f807cb29472d0924149e39d6ec8ad90e6a2 (patch) | |
| tree | 47e42f8cdfc83aaa3b706e06862c3efa4ba16745 /gnuradio-core/src/python/gnuradio/blksimpl/gmsk2.py | |
| parent | 04bb51ec4f1539c51c861b7fcad2ca8047a872a3 (diff) | |
Merged changes from eb/digital-wip into trunk.
This includes:
* renaming gnuradio-examples/python/gmsk2 to gnuradio-examples/python/digital
* refactoring the digital data tx and rx test code into benchmark_tx
and benchmark_rx. These accept a -m <modulation> argument.
<modulation> can currently be selected from gmsk, dbpsk, dqpsk
* Two new AGC blocks: gr_agc2: separate attack and delay rates;
gr_feedforward_agc: FIR-ish compressor. Normalizes to peak envelope.
* Working DBPSK mod/demod (works fine)
* Working DQPSK mod/demod (works, but still needs more work)
git-svn-id: http://gnuradio.org/svn/gnuradio/trunk@3662 221aa14e-8319-0410-a670-987f0aec2ac5
Diffstat (limited to 'gnuradio-core/src/python/gnuradio/blksimpl/gmsk2.py')
| -rw-r--r-- | gnuradio-core/src/python/gnuradio/blksimpl/gmsk2.py | 159 |
1 files changed, 0 insertions, 159 deletions
diff --git a/gnuradio-core/src/python/gnuradio/blksimpl/gmsk2.py b/gnuradio-core/src/python/gnuradio/blksimpl/gmsk2.py deleted file mode 100644 index 4fc033977b..0000000000 --- a/gnuradio-core/src/python/gnuradio/blksimpl/gmsk2.py +++ /dev/null @@ -1,159 +0,0 @@ -# -# GMSK modulation and demodulation. -# -# -# Copyright 2005,2006 Free Software Foundation, Inc. -# -# This file is part of GNU Radio -# -# GNU Radio is free software; you can redistribute it and/or modify -# it under the terms of the GNU General Public License as published by -# the Free Software Foundation; either version 2, or (at your option) -# any later version. -# -# GNU Radio is distributed in the hope that it will be useful, -# but WITHOUT ANY WARRANTY; without even the implied warranty of -# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the -# GNU General Public License for more details. -# -# You should have received a copy of the GNU General Public License -# along with GNU Radio; see the file COPYING. If not, write to -# the Free Software Foundation, Inc., 51 Franklin Street, -# Boston, MA 02110-1301, USA. -# - -# See gnuradio-examples/python/gmsk2 for examples - -from gnuradio import gr -from math import pi -import Numeric - -# ///////////////////////////////////////////////////////////////////////////// -# GMSK mod/demod with steams of bytes as data i/o -# ///////////////////////////////////////////////////////////////////////////// - -class gmsk2_mod(gr.hier_block): - - def __init__(self, fg, spb = 2, bt = 0.3): - """ - Hierarchical block for Gaussian Minimum Shift Key (GMSK) - modulation. - - The input is a byte stream (unsigned char) and the - output is the complex modulated signal at baseband. - - @param fg: flow graph - @type fg: flow graph - @param spb: samples per baud >= 2 - @type spb: integer - @param bt: Gaussian filter bandwidth * symbol time - @type bt: float - """ - if not isinstance(spb, int) or spb < 2: - raise TypeError, "sbp must be an integer >= 2" - self.spb = spb - - ntaps = 4 * spb # up to 3 bits in filter at once - sensitivity = (pi / 2) / spb # phase change per bit = pi / 2 - - # Turn it into NRZ data. - self.nrz = gr.bytes_to_syms() - - # Form Gaussian filter - - # Generate Gaussian response (Needs to be convolved with window below). - self.gaussian_taps = gr.firdes.gaussian( - 1, # gain - spb, # symbol_rate - bt, # bandwidth * symbol time - ntaps # number of taps - ) - - self.sqwave = (1,) * spb # rectangular window - self.taps = Numeric.convolve(Numeric.array(self.gaussian_taps),Numeric.array(self.sqwave)) - self.gaussian_filter = gr.interp_fir_filter_fff(spb, self.taps) - - # FM modulation - self.fmmod = gr.frequency_modulator_fc(sensitivity) - - # Connect - fg.connect(self.nrz, self.gaussian_filter, self.fmmod) - - # Initialize base class - gr.hier_block.__init__(self, fg, self.nrz, self.fmmod) - - def samples_per_baud(self): - return self.spb - - def bits_per_baud(self=None): # staticmethod that's also callable on an instance - return 1 - bits_per_baud = staticmethod(bits_per_baud) # make it a static method. RTFM - - -class gmsk2_demod(gr.hier_block): - - def __init__(self, fg, spb=2, omega=None, gain_mu=0.03, mu=0.5, - omega_relative_limit=0.000200, freq_error=0.0): - """ - Hierarchical block for Gaussian Minimum Shift Key (GMSK) - demodulation. - - The input is the complex modulated signal at baseband. - The output is a stream of symbols ready to be sliced at zero. - - @param fg: flow graph - @type fg: flow graph - @param spb: samples per baud - @type spb: integer - - Clock recovery parameters. These all have reasonble defaults. - - @param omega: nominal relative freq (defaults to spb) - @type omega: float - @param gain_mu: controls rate of mu adjustment - @type gain_mu: float - @param mu: fractional delay [0.0, 1.0] - @type mu: float - @param omega_relative_limit: sets max variation in omega - @type omega_relative_limit: float, typically 0.000200 (200 ppm) - @param freq_error: bit rate error as a fraction - @param float - """ - if spb < 2: - raise TypeError, "sbp >= 2" - self.spb = spb - - if omega is None: - omega = spb*(1+freq_error) - - gain_omega = .25*gain_mu*gain_mu # critically damped - - # Automatic gain control - self.preamp = gr.multiply_const_cc(10e-5) - self.agc = gr.agc_cc(1e-3, 1, 1, 1000) - - # Demodulate FM - sensitivity = (pi / 2) / spb - self.fmdemod = gr.quadrature_demod_cf(1.0 / sensitivity) - - alpha = 0.0008 - - # the clock recovery block tracks the symbol clock and resamples as needed. - # the output of the block is a stream of soft symbols (float) - self.clock_recovery = gr.clock_recovery_mm_ff(omega, gain_omega, mu, gain_mu, - omega_relative_limit) - - # slice the floats at 0, outputting 1 bit (the LSB of the output byte) per sample - self.slicer = gr.binary_slicer_fb() - - fg.connect(self.preamp, self.agc, self.fmdemod, self.clock_recovery, self.slicer) - - # Initialize base class - gr.hier_block.__init__(self, fg, self.preamp, self.slicer) - - def samples_per_baud(self): - return self.spb - - def bits_per_baud(self=None): # staticmethod that's also callable on an instance - return 1 - bits_per_baud = staticmethod(bits_per_baud) # make it a static method. RTFM |