Merged r4429:4857 from developer branch jcorgan/dect into trunk, passes distcheck.

git-svn-id: http://gnuradio.org/svn/gnuradio/trunk@4858 221aa14e-8319-0410-a670-987f0aec2ac5

1 files changed, 300 insertions, 0 deletions

diff --git a/gnuradio-examples/python/hier/dect/gmsk2.py b/gnuradio-examples/python/hier/dect/gmsk2.py
new file mode 100644
index 000000000..578873eed
--- /dev/null
+++ b/gnuradio-examples/python/hier/dect/gmsk2.py
@@ -0,0 +1,300 @@
+#
+# GMSK modulation and demodulation.  
+#
+#
+# Copyright 2005,2006,2007 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/digital for examples
+
+from gnuradio import gr
+from gnuradio import modulation_utils
+from math import pi
+import Numeric
+from pprint import pprint
+import inspect
+
+# default values (used in __init__ and add_options)
+_def_samples_per_symbol = 2
+_def_bt = 0.35
+_def_verbose = False
+_def_log = False
+
+_def_gain_mu = 0.05
+_def_mu = 0.5
+_def_freq_error = 0.0
+_def_omega_relative_limit = 0.005
+
+
+# /////////////////////////////////////////////////////////////////////////////
+#                              GMSK modulator
+# /////////////////////////////////////////////////////////////////////////////
+
+class gmsk2_mod(gr.hier_block2):
+
+    def __init__(self,
+                 samples_per_symbol=_def_samples_per_symbol,
+                 bt=_def_bt,
+                 verbose=_def_verbose,
+                 log=_def_log):
+        """
+	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 samples_per_symbol: samples per baud >= 2
+	@type samples_per_symbol: integer
+	@param bt: Gaussian filter bandwidth * symbol time
+	@type bt: float
+        @param verbose: Print information about modulator?
+        @type verbose: bool
+        @param debug: Print modualtion data to files?
+        @type debug: bool       
+	"""
+        gr.hier_block2.__init__(self,
+                                "gmsk2_mod",                               # Block typename
+                                gr.io_signature(1,1,gr.sizeof_char),       # Input signature
+                                gr.io_signature(1,1,gr.sizeof_gr_complex)) # Output signature
+
+        self._samples_per_symbol = samples_per_symbol
+        self._bt = bt
+
+        if not isinstance(samples_per_symbol, int) or samples_per_symbol < 2:
+            raise TypeError, ("samples_per_symbol must be an integer >= 2, is %r" % (samples_per_symbol,))
+
+	ntaps = 4 * samples_per_symbol			# up to 3 bits in filter at once
+	sensitivity = (pi / 2) / samples_per_symbol	# 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
+		samples_per_symbol,    # symbol_rate
+		bt,		       # bandwidth * symbol time
+		ntaps	               # number of taps
+		)
+
+	self.sqwave = (1,) * samples_per_symbol       # rectangular window
+	self.taps = Numeric.convolve(Numeric.array(self.gaussian_taps),Numeric.array(self.sqwave))
+	self.gaussian_filter = gr.interp_fir_filter_fff(samples_per_symbol, self.taps)
+
+	# FM modulation
+	self.fmmod = gr.frequency_modulator_fc(sensitivity)
+		
+        if verbose:
+            self._print_verbage()
+         
+	# Define and connect components
+        self.define_component("nrz", self.nrz)
+        self.define_component("filter", self.gaussian_filter)
+        self.define_component("fmmod", self.fmmod)
+        self.connect("self", 0, "nrz", 0)
+        self.connect("nrz", 0, "filter", 0)
+        self.connect("filter", 0, "fmmod", 0)
+        self.connect("fmmod", 0, "self", 0)
+
+        if log:
+            self._setup_logging()
+
+    def samples_per_symbol(self):
+        return self._samples_per_symbol
+
+    def bits_per_symbol(self=None):     # staticmethod that's also callable on an instance
+        return 1
+    bits_per_symbol = staticmethod(bits_per_symbol)      # make it a static method.
+
+
+    def _print_verbage(self):
+        print "bits per symbol = %d" % self.bits_per_symbol()
+        print "Gaussian filter bt = %.2f" % self._bt
+
+
+    def _setup_logging(self):
+        print "Modulation logging turned on."
+        self.define_component("nrz_log", gr.file_sink(gr.sizeof_float, "nrz.dat"))
+        self.define_component("filter_log", gr.file_sink(gr.sizeof_float, "gaussian_filter.dat"))
+        self.define_component("fmmod_log", gr.file_sink(gr.sizeof_gr_complex, "fmmod.dat"))
+        self.connect("nrz", 0, "nrz_log", 0)
+        self.connect("filter", 0, "filter_log", 0)
+        self.connect("fmmod", 0, "fmmod_log", 0)
+
+    def add_options(parser):
+        """
+        Adds GMSK modulation-specific options to the standard parser
+        """
+        parser.add_option("", "--bt", type="float", default=_def_bt,
+                          help="set bandwidth-time product [default=%default] (GMSK)")
+    add_options=staticmethod(add_options)
+
+    # FIXME: figure out what has to change for gr.hier_block2 version
+    #def extract_kwargs_from_options(options):
+    #    """
+    #    Given command line options, create dictionary suitable for passing to __init__
+    #    """
+    #    return modulation_utils.extract_kwargs_from_options(gmsk_mod.__init__,
+    #                                                        ('self', 'fg'), options)
+    #extract_kwargs_from_options=staticmethod(extract_kwargs_from_options)
+
+
+# /////////////////////////////////////////////////////////////////////////////
+#                            GMSK demodulator
+# /////////////////////////////////////////////////////////////////////////////
+
+class gmsk2_demod(gr.hier_block2):
+
+    def __init__(self,
+                 samples_per_symbol=_def_samples_per_symbol,
+                 gain_mu=_def_gain_mu,
+                 mu=_def_mu,
+                 omega_relative_limit=_def_omega_relative_limit,
+                 freq_error=_def_freq_error,
+                 verbose=_def_verbose,
+                 log=_def_log):
+        """
+	Hierarchical block for Gaussian Minimum Shift Key (GMSK)
+	demodulation.
+
+	The input is the complex modulated signal at baseband.
+	The output is a stream of bits packed 1 bit per byte (the LSB)
+
+	@param samples_per_symbol: samples per baud
+	@type samples_per_symbol: integer
+        @param verbose: Print information about modulator?
+        @type verbose: bool
+        @param log: Print modualtion data to files?
+        @type log: bool 
+
+        Clock recovery parameters.  These all have reasonble defaults.
+        
+        @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
+	"""
+
+        gr.hier_block2.__init__(self,
+                                "gmsk2_demod",                             # Block typename
+                                gr.io_signature(1,1,gr.sizeof_gr_complex), # Input signature
+                                gr.io_signature(1,1,gr.sizeof_char))       # Output signature
+                                
+        self._samples_per_symbol = samples_per_symbol
+        self._gain_mu = gain_mu
+        self._mu = mu
+        self._omega_relative_limit = omega_relative_limit
+        self._freq_error = freq_error
+        
+        if samples_per_symbol < 2:
+            raise TypeError, "samples_per_symbol >= 2, is %f" % samples_per_symbol
+
+        self._omega = samples_per_symbol*(1+self._freq_error)
+
+	self._gain_omega = .25 * self._gain_mu * self._gain_mu        # critically damped
+
+	# Demodulate FM
+	sensitivity = (pi / 2) / samples_per_symbol
+	self.fmdemod = gr.quadrature_demod_cf(1.0 / sensitivity)
+
+	# 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(self._omega, self._gain_omega,
+                                                      self._mu, self._gain_mu,
+                                                      self._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()
+
+        if verbose:
+            self._print_verbage()
+
+        # Define and connect components
+        self.define_component("fmdemod", self.fmdemod)
+        self.define_component("clock_recovery", self.clock_recovery)
+        self.define_component("slicer", self.slicer)
+        self.connect("self", 0, "fmdemod", 0)
+        self.connect("fmdemod", 0, "clock_recovery", 0)
+        self.connect("clock_recovery", 0, "slicer", 0)
+        self.connect("slicer", 0, "self", 0)
+
+        if log:
+            self._setup_logging()
+
+    def samples_per_symbol(self):
+        return self._samples_per_symbol
+
+    def bits_per_symbol(self=None):   # staticmethod that's also callable on an instance
+        return 1
+    bits_per_symbol = staticmethod(bits_per_symbol)      # make it a static method.
+
+
+    def _print_verbage(self):
+        print "bits per symbol = %d" % self.bits_per_symbol()
+        print "M&M clock recovery omega = %f" % self._omega
+        print "M&M clock recovery gain mu = %f" % self._gain_mu
+        print "M&M clock recovery mu = %f" % self._mu
+        print "M&M clock recovery omega rel. limit = %f" % self._omega_relative_limit
+        print "frequency error = %f" % self._freq_error
+
+
+    def _setup_logging(self):
+        print "Demodulation logging turned on."
+        self.define_component("fmdemod_log", gr.file_sink(gr.sizeof_float, "fmdemod.dat"))
+        self.define_component("clock_recovery_log", gr.file_sink(gr.sizeof_float, "clock_recovery.dat"))
+        self.define_component("slicer_log", gr.file_sink(gr.sizeof_char, "slicer.dat"))
+        self.connect("fmdemod", 0, "fmdemod_log", 0)
+        self.connect("clock_recovery", 0, "clock_recovery_log", 0)
+        self.connect("slicer", 0, "slicer_log", 0)
+
+    def add_options(parser):
+        """
+        Adds GMSK demodulation-specific options to the standard parser
+        """
+        parser.add_option("", "--gain-mu", type="float", default=_def_gain_mu,
+                          help="M&M clock recovery gain mu [default=%default] (GMSK/PSK)")
+        parser.add_option("", "--mu", type="float", default=_def_mu,
+                          help="M&M clock recovery mu [default=%default] (GMSK/PSK)")
+        parser.add_option("", "--omega-relative-limit", type="float", default=_def_omega_relative_limit,
+                          help="M&M clock recovery omega relative limit [default=%default] (GMSK/PSK)")
+        parser.add_option("", "--freq-error", type="float", default=_def_freq_error,
+                          help="M&M clock recovery frequency error [default=%default] (GMSK)")
+    add_options=staticmethod(add_options)
+
+    # FIXME: figure out what this is for gr.hier_block2 version
+    #def extract_kwargs_from_options(options):
+    #    """
+    #    Given command line options, create dictionary suitable for passing to __init__
+    #    """
+    #    return modulation_utils.extract_kwargs_from_options(gmsk_demod.__init__,
+    #                                                        ('self', 'fg'), options)
+    #extract_kwargs_from_options=staticmethod(extract_kwargs_from_options)
+
+#
+# Add these to the mod/demod registry
+#
+modulation_utils.add_type_1_mod('gmsk2', gmsk2_mod)
+modulation_utils.add_type_1_demod('gmsk2', gmsk2_demod)