digital: moved narrowband examples to their own directory (to make room for OFDM examples).

1 files changed, 126 insertions, 0 deletions

diff --git a/gr-digital/examples/narrowband/transmit_path.py b/gr-digital/examples/narrowband/transmit_path.py
new file mode 100644
index 000000000..4d6162ed6
--- /dev/null
+++ b/gr-digital/examples/narrowband/transmit_path.py
@@ -0,0 +1,126 @@
+#
+# Copyright 2005-2007,2011 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 3, 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.
+# 
+
+from gnuradio import gr
+from gnuradio import eng_notation
+from gnuradio import digital
+
+import copy
+import sys
+
+# /////////////////////////////////////////////////////////////////////////////
+#                              transmit path
+# /////////////////////////////////////////////////////////////////////////////
+
+class transmit_path(gr.hier_block2):
+    def __init__(self, modulator_class, options):
+        '''
+        See below for what options should hold
+        '''
+	gr.hier_block2.__init__(self, "transmit_path",
+				gr.io_signature(0,0,0),
+				gr.io_signature(1,1,gr.sizeof_gr_complex))
+        
+        options = copy.copy(options)    # make a copy so we can destructively modify
+
+        self._verbose      = options.verbose
+        self._tx_amplitude = options.tx_amplitude   # digital amplitude sent to USRP
+        self._bitrate      = options.bitrate        # desired bit rate
+        self._modulator_class = modulator_class     # the modulator_class we are using
+
+        # Get mod_kwargs
+        mod_kwargs = self._modulator_class.extract_kwargs_from_options(options)
+        
+        # transmitter
+	self.modulator = self._modulator_class(**mod_kwargs)
+        
+        self.packet_transmitter = \
+            digital.mod_pkts(self.modulator,
+                             access_code=None,
+                             msgq_limit=4,
+                             pad_for_usrp=True)
+
+        self.amp = gr.multiply_const_cc(1)
+        self.set_tx_amplitude(self._tx_amplitude)
+
+        # Display some information about the setup
+        if self._verbose:
+            self._print_verbage()
+
+        # Connect components in the flowgraph
+        self.connect(self.packet_transmitter, self.amp, self)
+
+    def set_tx_amplitude(self, ampl):
+        """
+        Sets the transmit amplitude sent to the USRP in volts
+        @param: ampl 0 <= ampl < 1.
+        """
+        self._tx_amplitude = max(0.0, min(ampl, 1))
+        self.amp.set_k(self._tx_amplitude)
+        
+    def send_pkt(self, payload='', eof=False):
+        """
+        Calls the transmitter method to send a packet
+        """
+        return self.packet_transmitter.send_pkt(payload, eof)
+        
+    def bitrate(self):
+        return self._bitrate
+
+    def samples_per_symbol(self):
+        return self.modulator._samples_per_symbol
+
+    def differential(self):
+        return self.modulator._differential
+
+    def add_options(normal, expert):
+        """
+        Adds transmitter-specific options to the Options Parser
+        """
+        if not normal.has_option('--bitrate'):
+            normal.add_option("-r", "--bitrate", type="eng_float",
+                              default=100e3,
+                              help="specify bitrate [default=%default].")
+        normal.add_option("", "--tx-amplitude", type="eng_float",
+                          default=0.250, metavar="AMPL",
+                          help="set transmitter digital amplitude: 0 <= AMPL < 1 [default=%default]")
+        normal.add_option("-v", "--verbose", action="store_true",
+                          default=False)
+
+        expert.add_option("-S", "--samples-per-symbol", type="float",
+                          default=2,
+                          help="set samples/symbol [default=%default]")
+        expert.add_option("", "--log", action="store_true",
+                          default=False,
+                          help="Log all parts of flow graph to file (CAUTION: lots of data)")
+
+    # Make a static method to call before instantiation
+    add_options = staticmethod(add_options)
+
+    def _print_verbage(self):
+        """
+        Prints information about the transmit path
+        """
+        print "Tx amplitude     %s"    % (self._tx_amplitude)
+        print "modulation:      %s"    % (self._modulator_class.__name__)
+        print "bitrate:         %sb/s" % (eng_notation.num_to_str(self._bitrate))
+        print "samples/symbol:  %.4f"  % (self.samples_per_symbol())
+        print "Differential:    %s"    % (self.differential())