Imported Upstream version 3.2.2

[debian/gnuradio] / gnuradio-core / src / python / gnuradio / blks2impl / standard_squelch.py

diff --git a/gnuradio-core/src/python/gnuradio/blks2impl/standard_squelch.py b/gnuradio-core/src/python/gnuradio/blks2impl/standard_squelch.py
new file mode 100644 (file)
index 0000000..c5fdc01
--- /dev/null
+++ b/gnuradio-core/src/python/gnuradio/blks2impl/standard_squelch.py
@@ -0,0 +1,76 @@
+#
+# Copyright 2005,2007 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 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.
+# 
+
+import math
+from gnuradio import gr, optfir
+
+class standard_squelch(gr.hier_block2):
+    def __init__(self, audio_rate):
+       gr.hier_block2.__init__(self, "standard_squelch",
+                               gr.io_signature(1, 1, gr.sizeof_float), # Input signature
+                               gr.io_signature(1, 1, gr.sizeof_float)) # Output signature
+    
+        self.input_node = gr.add_const_ff(0)          # FIXME kludge
+        
+        self.low_iir = gr.iir_filter_ffd((0.0193,0,-0.0193),(1,1.9524,-0.9615))
+        self.low_square = gr.multiply_ff()
+        self.low_smooth = gr.single_pole_iir_filter_ff(1/(0.01*audio_rate))   # 100ms time constant
+
+        self.hi_iir = gr.iir_filter_ffd((0.0193,0,-0.0193),(1,1.3597,-0.9615))
+        self.hi_square = gr.multiply_ff()
+        self.hi_smooth = gr.single_pole_iir_filter_ff(1/(0.01*audio_rate))
+
+        self.sub = gr.sub_ff();
+        self.add = gr.add_ff();
+        self.gate = gr.threshold_ff(0.3,0.43,0)
+        self.squelch_lpf = gr.single_pole_iir_filter_ff(1/(0.01*audio_rate))
+
+        self.div = gr.divide_ff()
+        self.squelch_mult = gr.multiply_ff()
+
+       self.connect (self, self.input_node)
+        self.connect (self.input_node, (self.squelch_mult, 0))
+
+        self.connect (self.input_node,self.low_iir)
+        self.connect (self.low_iir,(self.low_square,0))
+        self.connect (self.low_iir,(self.low_square,1))
+        self.connect (self.low_square,self.low_smooth,(self.sub,0))
+        self.connect (self.low_smooth, (self.add,0))
+
+        self.connect (self.input_node,self.hi_iir)
+        self.connect (self.hi_iir,(self.hi_square,0))
+        self.connect (self.hi_iir,(self.hi_square,1))
+        self.connect (self.hi_square,self.hi_smooth,(self.sub,1))
+        self.connect (self.hi_smooth, (self.add,1))
+
+        self.connect (self.sub, (self.div, 0))
+        self.connect (self.add, (self.div, 1))
+        self.connect (self.div, self.gate, self.squelch_lpf, (self.squelch_mult,1))
+       self.connect (self.squelch_mult, self)
+
+    def set_threshold(self, threshold):
+        self.gate.set_hi(threshold)
+
+    def threshold(self):
+        return self.gate.hi()
+    
+    def squelch_range(self):
+        return (0.0, 1.0, 1.0/100)