1 files changed, 105 insertions, 0 deletions
diff --git a/gr-digital/examples/ofdm/receive_path.py b/gr-digital/examples/ofdm/receive_path.py
new file mode 100644
index 000000000..e1c7868a0
--- /dev/null
+++ b/gr-digital/examples/ofdm/receive_path.py
@@ -0,0 +1,105 @@
+#
+# Copyright 2005,2006,2011 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
+
+# /////////////////////////////////////////////////////////////////////////////
+#                              receive path
+# /////////////////////////////////////////////////////////////////////////////
+
+class receive_path(gr.hier_block2):
+    def __init__(self, rx_callback, options):
+
+	gr.hier_block2.__init__(self, "receive_path",
+				gr.io_signature(1, 1, gr.sizeof_gr_complex),
+				gr.io_signature(0, 0, 0))
+
+
+        options = copy.copy(options)    # make a copy so we can destructively modify
+
+        self._verbose     = options.verbose
+        self._log         = options.log
+        self._rx_callback = rx_callback      # this callback is fired when there's a packet available
+
+        # receiver
+        self.ofdm_rx = digital.ofdm_demod(options,
+                                          callback=self._rx_callback)
+
+        # Carrier Sensing Blocks
+        alpha = 0.001
+        thresh = 30   # in dB, will have to adjust
+        self.probe = gr.probe_avg_mag_sqrd_c(thresh,alpha)
+
+        self.connect(self, self.ofdm_rx)
+        self.connect(self.ofdm_rx, self.probe)
+
+        # Display some information about the setup
+        if self._verbose:
+            self._print_verbage()
+        
+    def carrier_sensed(self):
+        """
+        Return True if we think carrier is present.
+        """
+        #return self.probe.level() > X
+        return self.probe.unmuted()
+
+    def carrier_threshold(self):
+        """
+        Return current setting in dB.
+        """
+        return self.probe.threshold()
+
+    def set_carrier_threshold(self, threshold_in_db):
+        """
+        Set carrier threshold.
+
+        @param threshold_in_db: set detection threshold
+        @type threshold_in_db:  float (dB)
+        """
+        self.probe.set_threshold(threshold_in_db)
+    
+        
+    def add_options(normal, expert):
+        """
+        Adds receiver-specific options to the Options Parser
+        """
+        normal.add_option("-W", "--bandwidth", type="eng_float",
+                          default=500e3,
+                          help="set symbol bandwidth [default=%default]")
+        normal.add_option("-v", "--verbose", action="store_true", default=False)
+        expert.add_option("", "--log", action="store_true", default=False,
+                          help="Log all parts of flow graph to files (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 receive path
+        """
+        pass