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diff --git a/gnuradio-core/src/python/gnuradio/blksimpl/gmsk2.py b/gnuradio-core/src/python/gnuradio/blksimpl/gmsk2.py
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+++ b/gnuradio-core/src/python/gnuradio/blksimpl/gmsk2.py
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+#
+# 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., 59 Temple Place - Suite 330,
+# Boston, MA 02111-1307, 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