Added new configurable block for demapping of control channels.

12 files changed, 1147 insertions, 308 deletions

diff --git a/examples/receiver_file.grc b/examples/receiver_file.grc
index af657d8..6bc0516 100644
--- a/examples/receiver_file.grc
+++ b/examples/receiver_file.grc
@@ -1,63 +1,229 @@
 <?xml version='1.0' encoding='ASCII'?>
+<?grc format='1' created='3.7.6'?>
 <flow_graph>
-  <timestamp>Thu Nov  6 14:42:26 2014</timestamp>
+  <timestamp>Wed Aug 13 19:03:06 2014</timestamp>
   <block>
-    <key>options</key>
+    <key>parameter</key>
     <param>
       <key>id</key>
-      <value>gsm_receiver_file</value>
+      <value>input_file_name</value>
     </param>
     <param>
       <key>_enabled</key>
       <value>True</value>
     </param>
     <param>
-      <key>title</key>
+      <key>label</key>
+      <value>input_file_name</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>input.cfile</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>string</value>
+    </param>
+    <param>
+      <key>short_id</key>
+      <value>i</value>
+    </param>
+    <param>
+      <key>alias</key>
       <value></value>
     </param>
     <param>
-      <key>author</key>
+      <key>_coordinate</key>
+      <value>(184, -5)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable</key>
+    <param>
+      <key>id</key>
+      <value>AGCH</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>4</value>
+    </param>
+    <param>
+      <key>alias</key>
       <value></value>
     </param>
     <param>
-      <key>description</key>
+      <key>_coordinate</key>
+      <value>(808, -5)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable</key>
+    <param>
+      <key>id</key>
+      <value>PCH</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>5</value>
+    </param>
+    <param>
+      <key>alias</key>
       <value></value>
     </param>
     <param>
-      <key>window_size</key>
-      <value>1280, 1024</value>
+      <key>_coordinate</key>
+      <value>(872, -5)</value>
     </param>
     <param>
-      <key>generate_options</key>
-      <value>wx_gui</value>
+      <key>_rotation</key>
+      <value>0</value>
     </param>
+  </block>
+  <block>
+    <key>variable</key>
     <param>
-      <key>category</key>
-      <value>Custom</value>
+      <key>id</key>
+      <value>RACH</value>
     </param>
     <param>
-      <key>run_options</key>
-      <value>run</value>
+      <key>_enabled</key>
+      <value>True</value>
     </param>
     <param>
-      <key>run</key>
+      <key>value</key>
+      <value>3</value>
+    </param>
+    <param>
+      <key>alias</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(744, -5)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable</key>
+    <param>
+      <key>id</key>
+      <value>SDCCH</value>
+    </param>
+    <param>
+      <key>_enabled</key>
       <value>True</value>
     </param>
     <param>
-      <key>max_nouts</key>
+      <key>value</key>
+      <value>6</value>
+    </param>
+    <param>
+      <key>alias</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(936, -5)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
       <value>0</value>
     </param>
+  </block>
+  <block>
+    <key>variable</key>
+    <param>
+      <key>id</key>
+      <value>CCCH</value>
+    </param>
     <param>
-      <key>realtime_scheduling</key>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>2</value>
+    </param>
+    <param>
+      <key>alias</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(680, -5)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable</key>
+    <param>
+      <key>id</key>
+      <value>BCCH</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>1</value>
+    </param>
+    <param>
+      <key>alias</key>
       <value></value>
     </param>
     <param>
+      <key>_coordinate</key>
+      <value>(616, -5)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable</key>
+    <param>
+      <key>id</key>
+      <value>CHANNEL_UNKNOWN</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>0</value>
+    </param>
+    <param>
       <key>alias</key>
       <value></value>
     </param>
     <param>
       <key>_coordinate</key>
-      <value>(10, 10)</value>
+      <value>(480, -5)</value>
     </param>
     <param>
       <key>_rotation</key>
@@ -96,7 +262,7 @@
     </param>
     <param>
       <key>_coordinate</key>
-      <value>(311, 10)</value>
+      <value>(296, -5)</value>
     </param>
     <param>
       <key>_rotation</key>
@@ -135,7 +301,7 @@
     </param>
     <param>
       <key>_coordinate</key>
-      <value>(656, 8)</value>
+      <value>(376, -5)</value>
     </param>
     <param>
       <key>_rotation</key>
@@ -143,61 +309,62 @@
     </param>
   </block>
   <block>
-    <key>gsm_message_printer</key>
+    <key>options</key>
     <param>
       <key>id</key>
-      <value>gsm_message_printer_0</value>
+      <value>gsm_receiver_file</value>
     </param>
     <param>
       <key>_enabled</key>
       <value>True</value>
     </param>
     <param>
-      <key>alias</key>
+      <key>title</key>
       <value></value>
     </param>
     <param>
-      <key>affinity</key>
+      <key>author</key>
       <value></value>
     </param>
     <param>
-      <key>_coordinate</key>
-      <value>(1130, 196)</value>
+      <key>description</key>
+      <value></value>
     </param>
     <param>
-      <key>_rotation</key>
-      <value>0</value>
+      <key>window_size</key>
+      <value>1280, 1024</value>
     </param>
-  </block>
-  <block>
-    <key>gsm_control_channels_decoder</key>
     <param>
-      <key>id</key>
-      <value>gsm_control_channels_decoder_0</value>
+      <key>generate_options</key>
+      <value>no_gui</value>
     </param>
     <param>
-      <key>_enabled</key>
-      <value>True</value>
+      <key>category</key>
+      <value>Custom</value>
     </param>
     <param>
-      <key>alias</key>
-      <value></value>
+      <key>run_options</key>
+      <value>run</value>
     </param>
     <param>
-      <key>affinity</key>
-      <value></value>
+      <key>run</key>
+      <value>True</value>
     </param>
     <param>
-      <key>minoutbuf</key>
+      <key>max_nouts</key>
       <value>0</value>
     </param>
     <param>
-      <key>maxoutbuf</key>
-      <value>0</value>
+      <key>realtime_scheduling</key>
+      <value></value>
+    </param>
+    <param>
+      <key>alias</key>
+      <value></value>
     </param>
     <param>
       <key>_coordinate</key>
-      <value>(908, 196)</value>
+      <value>(0, -5)</value>
     </param>
     <param>
       <key>_rotation</key>
@@ -205,34 +372,22 @@
     </param>
   </block>
   <block>
-    <key>blocks_socket_pdu</key>
+    <key>gsm_clock_offset_control</key>
     <param>
       <key>id</key>
-      <value>blocks_socket_pdu_0</value>
+      <value>gsm_clock_offset_control_0</value>
     </param>
     <param>
       <key>_enabled</key>
       <value>True</value>
     </param>
     <param>
-      <key>type</key>
-      <value>"UDP_CLIENT"</value>
-    </param>
-    <param>
-      <key>host</key>
-      <value>127.0.0.1</value>
-    </param>
-    <param>
-      <key>port</key>
-      <value>4729</value>
-    </param>
-    <param>
-      <key>mtu</key>
-      <value>10000</value>
+      <key>fc</key>
+      <value>fc</value>
     </param>
     <param>
-      <key>tcp_no_delay</key>
-      <value>False</value>
+      <key>samp_rate</key>
+      <value>samp_rate</value>
     </param>
     <param>
       <key>alias</key>
@@ -252,26 +407,38 @@
     </param>
     <param>
       <key>_coordinate</key>
-      <value>(1138, 278)</value>
+      <value>(240, 219)</value>
     </param>
     <param>
       <key>_rotation</key>
-      <value>0</value>
+      <value>180</value>
     </param>
   </block>
   <block>
-    <key>gsm_get_bcch_or_ccch_bursts</key>
+    <key>gsm_input</key>
     <param>
       <key>id</key>
-      <value>gsm_get_bcch_or_ccch_bursts_0</value>
+      <value>gsm_input_0</value>
     </param>
     <param>
       <key>_enabled</key>
       <value>True</value>
     </param>
     <param>
-      <key>d_fn51_start</key>
-      <value>2</value>
+      <key>ppm</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>osr</key>
+      <value>4</value>
+    </param>
+    <param>
+      <key>fc</key>
+      <value>fc</value>
+    </param>
+    <param>
+      <key>samp_rate_in</key>
+      <value>samp_rate</value>
     </param>
     <param>
       <key>alias</key>
@@ -291,7 +458,7 @@
     </param>
     <param>
       <key>_coordinate</key>
-      <value>(637, 192)</value>
+      <value>(176, 128)</value>
     </param>
     <param>
       <key>_rotation</key>
@@ -299,22 +466,30 @@
     </param>
   </block>
   <block>
-    <key>gsm_clock_offset_control</key>
+    <key>blocks_file_source</key>
     <param>
       <key>id</key>
-      <value>gsm_clock_offset_control_0</value>
+      <value>blocks_file_source_0</value>
     </param>
     <param>
       <key>_enabled</key>
       <value>True</value>
     </param>
     <param>
-      <key>fc</key>
-      <value>fc</value>
+      <key>file</key>
+      <value>input_file_name</value>
     </param>
     <param>
-      <key>samp_rate</key>
-      <value>samp_rate</value>
+      <key>type</key>
+      <value>complex</value>
+    </param>
+    <param>
+      <key>repeat</key>
+      <value>False</value>
+    </param>
+    <param>
+      <key>vlen</key>
+      <value>1</value>
     </param>
     <param>
       <key>alias</key>
@@ -334,11 +509,11 @@
     </param>
     <param>
       <key>_coordinate</key>
-      <value>(261, 307)</value>
+      <value>(-8, 115)</value>
     </param>
     <param>
       <key>_rotation</key>
-      <value>180</value>
+      <value>0</value>
     </param>
   </block>
   <block>
@@ -385,7 +560,7 @@
     </param>
     <param>
       <key>_coordinate</key>
-      <value>(414, 196)</value>
+      <value>(352, 112)</value>
     </param>
     <param>
       <key>_rotation</key>
@@ -393,30 +568,22 @@
     </param>
   </block>
   <block>
-    <key>gsm_input</key>
+    <key>gsm_universal_ctrl_chans_demapper</key>
     <param>
       <key>id</key>
-      <value>gsm_input_0</value>
+      <value>gsm_universal_ctrl_chans_demapper_0</value>
     </param>
     <param>
       <key>_enabled</key>
       <value>True</value>
     </param>
     <param>
-      <key>ppm</key>
-      <value>0</value>
-    </param>
-    <param>
-      <key>fc</key>
-      <value>fc</value>
-    </param>
-    <param>
-      <key>osr</key>
-      <value>4</value>
+      <key>starts_fn_mod51</key>
+      <value>[2,6,12,16,22,26,32,36,42,46]</value>
     </param>
     <param>
-      <key>samp_rate_in</key>
-      <value>samp_rate</value>
+      <key>channel_types</key>
+      <value>[BCCH,CCCH,CCCH,CCCH,CCCH,CCCH,CCCH,CCCH,CCCH,CCCH]</value>
     </param>
     <param>
       <key>alias</key>
@@ -436,7 +603,7 @@
     </param>
     <param>
       <key>_coordinate</key>
-      <value>(226, 213)</value>
+      <value>(536, 112)</value>
     </param>
     <param>
       <key>_rotation</key>
@@ -444,38 +611,34 @@
     </param>
   </block>
   <block>
-    <key>parameter</key>
+    <key>gsm_control_channels_decoder</key>
     <param>
       <key>id</key>
-      <value>input_file_name</value>
+      <value>gsm_control_channels_decoder_0</value>
     </param>
     <param>
       <key>_enabled</key>
       <value>True</value>
     </param>
     <param>
-      <key>label</key>
-      <value>input_file_name</value>
-    </param>
-    <param>
-      <key>value</key>
-      <value>input.cfile</value>
+      <key>alias</key>
+      <value></value>
     </param>
     <param>
-      <key>type</key>
-      <value>string</value>
+      <key>affinity</key>
+      <value></value>
     </param>
     <param>
-      <key>short_id</key>
-      <value>i</value>
+      <key>minoutbuf</key>
+      <value>0</value>
     </param>
     <param>
-      <key>alias</key>
-      <value></value>
+      <key>maxoutbuf</key>
+      <value>0</value>
     </param>
     <param>
       <key>_coordinate</key>
-      <value>(193, 11)</value>
+      <value>(784, 112)</value>
     </param>
     <param>
       <key>_rotation</key>
@@ -483,32 +646,16 @@
     </param>
   </block>
   <block>
-    <key>blocks_file_source</key>
+    <key>gsm_message_printer</key>
     <param>
       <key>id</key>
-      <value>blocks_file_source_0</value>
+      <value>gsm_message_printer_0</value>
     </param>
     <param>
       <key>_enabled</key>
       <value>True</value>
     </param>
     <param>
-      <key>file</key>
-      <value>input_file_name</value>
-    </param>
-    <param>
-      <key>type</key>
-      <value>complex</value>
-    </param>
-    <param>
-      <key>repeat</key>
-      <value>False</value>
-    </param>
-    <param>
-      <key>vlen</key>
-      <value>1</value>
-    </param>
-    <param>
       <key>alias</key>
       <value></value>
     </param>
@@ -517,16 +664,8 @@
       <value></value>
     </param>
     <param>
-      <key>minoutbuf</key>
-      <value>0</value>
-    </param>
-    <param>
-      <key>maxoutbuf</key>
-      <value>0</value>
-    </param>
-    <param>
       <key>_coordinate</key>
-      <value>(15, 201)</value>
+      <value>(1000, 112)</value>
     </param>
     <param>
       <key>_rotation</key>
@@ -540,44 +679,38 @@
     <sink_key>measurements</sink_key>
   </connection>
   <connection>
-    <source_block_id>gsm_receiver_0</source_block_id>
-    <sink_block_id>gsm_get_bcch_or_ccch_bursts_0</sink_block_id>
-    <source_key>C0</source_key>
-    <sink_key>bursts</sink_key>
-  </connection>
-  <connection>
-    <source_block_id>gsm_get_bcch_or_ccch_bursts_0</source_block_id>
-    <sink_block_id>gsm_control_channels_decoder_0</sink_block_id>
-    <source_key>bursts</source_key>
-    <sink_key>bursts</sink_key>
-  </connection>
-  <connection>
     <source_block_id>gsm_control_channels_decoder_0</source_block_id>
     <sink_block_id>gsm_message_printer_0</sink_block_id>
     <source_key>msgs</source_key>
     <sink_key>msgs</sink_key>
   </connection>
   <connection>
-    <source_block_id>gsm_control_channels_decoder_0</source_block_id>
-    <sink_block_id>blocks_socket_pdu_0</sink_block_id>
-    <source_key>msgs</source_key>
-    <sink_key>pdus</sink_key>
-  </connection>
-  <connection>
-    <source_block_id>blocks_file_source_0</source_block_id>
-    <sink_block_id>gsm_input_0</sink_block_id>
+    <source_block_id>gsm_input_0</source_block_id>
+    <sink_block_id>gsm_receiver_0</sink_block_id>
     <source_key>0</source_key>
     <sink_key>0</sink_key>
   </connection>
   <connection>
+    <source_block_id>gsm_universal_ctrl_chans_demapper_0</source_block_id>
+    <sink_block_id>gsm_control_channels_decoder_0</sink_block_id>
+    <source_key>bursts</source_key>
+    <sink_key>bursts</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>gsm_receiver_0</source_block_id>
+    <sink_block_id>gsm_universal_ctrl_chans_demapper_0</sink_block_id>
+    <source_key>C0</source_key>
+    <sink_key>bursts</sink_key>
+  </connection>
+  <connection>
     <source_block_id>gsm_clock_offset_control_0</source_block_id>
     <sink_block_id>gsm_input_0</sink_block_id>
     <source_key>ppm</source_key>
     <sink_key>ppm_in</sink_key>
   </connection>
   <connection>
-    <source_block_id>gsm_input_0</source_block_id>
-    <sink_block_id>gsm_receiver_0</sink_block_id>
+    <source_block_id>blocks_file_source_0</source_block_id>
+    <sink_block_id>gsm_input_0</sink_block_id>
     <source_key>0</source_key>
     <sink_key>0</sink_key>
   </connection>
diff --git a/examples/receiver_rtlsdr.grc b/examples/receiver_rtlsdr.grc
index beee92d..ae68d08 100644
--- a/examples/receiver_rtlsdr.grc
+++ b/examples/receiver_rtlsdr.grc
@@ -1,4 +1,5 @@
 <?xml version='1.0' encoding='ASCII'?>
+<?grc format='1' created='3.7.6'?>
 <flow_graph>
   <timestamp>Thu Nov  6 14:43:22 2014</timestamp>
   <block>
@@ -68,7 +69,7 @@
     <key>variable</key>
     <param>
       <key>id</key>
-      <value>samp_rate</value>
+      <value>AGCH</value>
     </param>
     <param>
       <key>_enabled</key>
@@ -76,7 +77,7 @@
     </param>
     <param>
       <key>value</key>
-      <value>1000000.026491</value>
+      <value>4</value>
     </param>
     <param>
       <key>alias</key>
@@ -84,7 +85,7 @@
     </param>
     <param>
       <key>_coordinate</key>
-      <value>(13, 86)</value>
+      <value>(944, 11)</value>
     </param>
     <param>
       <key>_rotation</key>
@@ -92,26 +93,53 @@
     </param>
   </block>
   <block>
-    <key>gsm_message_printer</key>
+    <key>variable</key>
     <param>
       <key>id</key>
-      <value>gsm_message_printer_1</value>
+      <value>RACH</value>
     </param>
     <param>
       <key>_enabled</key>
       <value>True</value>
     </param>
     <param>
+      <key>value</key>
+      <value>3</value>
+    </param>
+    <param>
       <key>alias</key>
       <value></value>
     </param>
     <param>
-      <key>affinity</key>
+      <key>_coordinate</key>
+      <value>(880, 11)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable</key>
+    <param>
+      <key>id</key>
+      <value>SDCCH</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>6</value>
+    </param>
+    <param>
+      <key>alias</key>
       <value></value>
     </param>
     <param>
       <key>_coordinate</key>
-      <value>(1131, 230)</value>
+      <value>(1072, 11)</value>
     </param>
     <param>
       <key>_rotation</key>
@@ -119,38 +147,53 @@
     </param>
   </block>
   <block>
-    <key>gsm_get_bcch_or_ccch_bursts</key>
+    <key>variable</key>
     <param>
       <key>id</key>
-      <value>gsm_get_bcch_or_ccch_bursts_0</value>
+      <value>PCH</value>
     </param>
     <param>
       <key>_enabled</key>
       <value>True</value>
     </param>
     <param>
-      <key>d_fn51_start</key>
-      <value>2</value>
+      <key>value</key>
+      <value>5</value>
     </param>
     <param>
       <key>alias</key>
       <value></value>
     </param>
     <param>
-      <key>affinity</key>
-      <value></value>
+      <key>_coordinate</key>
+      <value>(1008, 11)</value>
     </param>
     <param>
-      <key>minoutbuf</key>
+      <key>_rotation</key>
       <value>0</value>
     </param>
+  </block>
+  <block>
+    <key>variable</key>
     <param>
-      <key>maxoutbuf</key>
-      <value>0</value>
+      <key>id</key>
+      <value>samp_rate</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>1000000.026491</value>
+    </param>
+    <param>
+      <key>alias</key>
+      <value></value>
     </param>
     <param>
       <key>_coordinate</key>
-      <value>(650, 226)</value>
+      <value>(13, 86)</value>
     </param>
     <param>
       <key>_rotation</key>
@@ -158,34 +201,107 @@
     </param>
   </block>
   <block>
-    <key>gsm_control_channels_decoder</key>
+    <key>variable</key>
     <param>
       <key>id</key>
-      <value>gsm_control_channels_decoder_0</value>
+      <value>CCCH</value>
     </param>
     <param>
       <key>_enabled</key>
       <value>True</value>
     </param>
     <param>
+      <key>value</key>
+      <value>2</value>
+    </param>
+    <param>
       <key>alias</key>
       <value></value>
     </param>
     <param>
-      <key>affinity</key>
+      <key>_coordinate</key>
+      <value>(816, 11)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable</key>
+    <param>
+      <key>id</key>
+      <value>CHANNEL_UNKNOWN</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>alias</key>
       <value></value>
     </param>
     <param>
-      <key>minoutbuf</key>
+      <key>_coordinate</key>
+      <value>(616, 11)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
       <value>0</value>
     </param>
+  </block>
+  <block>
+    <key>variable</key>
     <param>
-      <key>maxoutbuf</key>
+      <key>id</key>
+      <value>BCCH</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>1</value>
+    </param>
+    <param>
+      <key>alias</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(752, 11)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
       <value>0</value>
     </param>
+  </block>
+  <block>
+    <key>gsm_message_printer</key>
+    <param>
+      <key>id</key>
+      <value>gsm_message_printer_1</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>alias</key>
+      <value></value>
+    </param>
+    <param>
+      <key>affinity</key>
+      <value></value>
+    </param>
     <param>
       <key>_coordinate</key>
-      <value>(910, 230)</value>
+      <value>(1131, 230)</value>
     </param>
     <param>
       <key>_rotation</key>
@@ -698,6 +814,10 @@
       <value>1024</value>
     </param>
     <param>
+      <key>freqhalf</key>
+      <value>True</value>
+    </param>
+    <param>
       <key>wintype</key>
       <value>firdes.WIN_BLACKMAN_hARRIS</value>
     </param>
@@ -746,6 +866,22 @@
       <value>True</value>
     </param>
     <param>
+      <key>tr_mode</key>
+      <value>qtgui.TRIG_MODE_FREE</value>
+    </param>
+    <param>
+      <key>tr_level</key>
+      <value>0.0</value>
+    </param>
+    <param>
+      <key>tr_chan</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>tr_tag</key>
+      <value>""</value>
+    </param>
+    <param>
       <key>label1</key>
       <value></value>
     </param>
@@ -974,6 +1110,92 @@
     </param>
   </block>
   <block>
+    <key>gsm_input</key>
+    <param>
+      <key>id</key>
+      <value>gsm_input_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>ppm</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>fc</key>
+      <value>fc</value>
+    </param>
+    <param>
+      <key>osr</key>
+      <value>4</value>
+    </param>
+    <param>
+      <key>samp_rate_in</key>
+      <value>samp_rate</value>
+    </param>
+    <param>
+      <key>alias</key>
+      <value></value>
+    </param>
+    <param>
+      <key>affinity</key>
+      <value></value>
+    </param>
+    <param>
+      <key>minoutbuf</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>maxoutbuf</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(268, 247)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>gsm_control_channels_decoder</key>
+    <param>
+      <key>id</key>
+      <value>gsm_control_channels_decoder_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>alias</key>
+      <value></value>
+    </param>
+    <param>
+      <key>affinity</key>
+      <value></value>
+    </param>
+    <param>
+      <key>minoutbuf</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>maxoutbuf</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(910, 230)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
     <key>gsm_receiver</key>
     <param>
       <key>id</key>
@@ -1025,30 +1247,22 @@
     </param>
   </block>
   <block>
-    <key>gsm_input</key>
+    <key>gsm_universal_ctrl_chans_demapper</key>
     <param>
       <key>id</key>
-      <value>gsm_input_0</value>
+      <value>gsm_universal_ctrl_chans_demapper_0</value>
     </param>
     <param>
       <key>_enabled</key>
       <value>True</value>
     </param>
     <param>
-      <key>ppm</key>
-      <value>0</value>
+      <key>starts_fn_mod51</key>
+      <value>[2,6,12,16,22,26,32,36,42,46]</value>
     </param>
     <param>
-      <key>fc</key>
-      <value>fc</value>
-    </param>
-    <param>
-      <key>osr</key>
-      <value>4</value>
-    </param>
-    <param>
-      <key>samp_rate_in</key>
-      <value>samp_rate</value>
+      <key>channel_types</key>
+      <value>[BCCH,CCCH,CCCH,CCCH,CCCH,CCCH,CCCH,CCCH,CCCH,CCCH]</value>
     </param>
     <param>
       <key>alias</key>
@@ -1068,7 +1282,7 @@
     </param>
     <param>
       <key>_coordinate</key>
-      <value>(268, 247)</value>
+      <value>(648, 232)</value>
     </param>
     <param>
       <key>_rotation</key>
@@ -1082,12 +1296,6 @@
     <sink_key>msgs</sink_key>
   </connection>
   <connection>
-    <source_block_id>gsm_get_bcch_or_ccch_bursts_0</source_block_id>
-    <sink_block_id>gsm_control_channels_decoder_0</sink_block_id>
-    <source_key>bursts</source_key>
-    <sink_key>bursts</sink_key>
-  </connection>
-  <connection>
     <source_block_id>gsm_control_channels_decoder_0</source_block_id>
     <sink_block_id>blocks_socket_pdu_0</sink_block_id>
     <source_key>msgs</source_key>
@@ -1119,14 +1327,20 @@
   </connection>
   <connection>
     <source_block_id>gsm_receiver_0</source_block_id>
-    <sink_block_id>gsm_get_bcch_or_ccch_bursts_0</sink_block_id>
-    <source_key>C0</source_key>
+    <sink_block_id>gsm_clock_offset_control_0</sink_block_id>
+    <source_key>measurements</source_key>
+    <sink_key>measurements</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>gsm_universal_ctrl_chans_demapper_0</source_block_id>
+    <sink_block_id>gsm_control_channels_decoder_0</sink_block_id>
+    <source_key>bursts</source_key>
     <sink_key>bursts</sink_key>
   </connection>
   <connection>
     <source_block_id>gsm_receiver_0</source_block_id>
-    <sink_block_id>gsm_clock_offset_control_0</sink_block_id>
-    <source_key>measurements</source_key>
-    <sink_key>measurements</sink_key>
+    <sink_block_id>gsm_universal_ctrl_chans_demapper_0</sink_block_id>
+    <source_key>C0</source_key>
+    <sink_key>bursts</sink_key>
   </connection>
 </flow_graph>
diff --git a/examples/receiver_usrp.grc b/examples/receiver_usrp.grc
index 7202f10..82f0109 100644
--- a/examples/receiver_usrp.grc
+++ b/examples/receiver_usrp.grc
@@ -1,4 +1,5 @@
 <?xml version='1.0' encoding='ASCII'?>
+<?grc format='1' created='3.7.6'?>
 <flow_graph>
   <timestamp>Thu Nov  6 14:43:18 2014</timestamp>
   <block>
@@ -68,6 +69,195 @@
     <key>variable</key>
     <param>
       <key>id</key>
+      <value>CHANNEL_UNKNOWN</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>alias</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(600, 11)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable</key>
+    <param>
+      <key>id</key>
+      <value>CCCH</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>2</value>
+    </param>
+    <param>
+      <key>alias</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(800, 11)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable</key>
+    <param>
+      <key>id</key>
+      <value>AGCH</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>4</value>
+    </param>
+    <param>
+      <key>alias</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(928, 11)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable</key>
+    <param>
+      <key>id</key>
+      <value>BCCH</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>1</value>
+    </param>
+    <param>
+      <key>alias</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(736, 11)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable</key>
+    <param>
+      <key>id</key>
+      <value>PCH</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>5</value>
+    </param>
+    <param>
+      <key>alias</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(992, 11)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable</key>
+    <param>
+      <key>id</key>
+      <value>SDCCH</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>6</value>
+    </param>
+    <param>
+      <key>alias</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(1056, 11)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable</key>
+    <param>
+      <key>id</key>
+      <value>RACH</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>3</value>
+    </param>
+    <param>
+      <key>alias</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(864, 11)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable</key>
+    <param>
+      <key>id</key>
       <value>samp_rate</value>
     </param>
     <param>
@@ -269,45 +459,6 @@
     </param>
   </block>
   <block>
-    <key>gsm_get_bcch_or_ccch_bursts</key>
-    <param>
-      <key>id</key>
-      <value>gsm_get_bcch_or_ccch_bursts_0</value>
-    </param>
-    <param>
-      <key>_enabled</key>
-      <value>True</value>
-    </param>
-    <param>
-      <key>d_fn51_start</key>
-      <value>2</value>
-    </param>
-    <param>
-      <key>alias</key>
-      <value></value>
-    </param>
-    <param>
-      <key>affinity</key>
-      <value></value>
-    </param>
-    <param>
-      <key>minoutbuf</key>
-      <value>0</value>
-    </param>
-    <param>
-      <key>maxoutbuf</key>
-      <value>0</value>
-    </param>
-    <param>
-      <key>_coordinate</key>
-      <value>(674, 268)</value>
-    </param>
-    <param>
-      <key>_rotation</key>
-      <value>0</value>
-    </param>
-  </block>
-  <block>
     <key>gsm_message_printer</key>
     <param>
       <key>id</key>
@@ -335,41 +486,6 @@
     </param>
   </block>
   <block>
-    <key>gsm_control_channels_decoder</key>
-    <param>
-      <key>id</key>
-      <value>gsm_control_channels_decoder_0</value>
-    </param>
-    <param>
-      <key>_enabled</key>
-      <value>True</value>
-    </param>
-    <param>
-      <key>alias</key>
-      <value></value>
-    </param>
-    <param>
-      <key>affinity</key>
-      <value></value>
-    </param>
-    <param>
-      <key>minoutbuf</key>
-      <value>0</value>
-    </param>
-    <param>
-      <key>maxoutbuf</key>
-      <value>0</value>
-    </param>
-    <param>
-      <key>_coordinate</key>
-      <value>(916, 272)</value>
-    </param>
-    <param>
-      <key>_rotation</key>
-      <value>0</value>
-    </param>
-  </block>
-  <block>
     <key>blocks_socket_pdu</key>
     <param>
       <key>id</key>
@@ -447,6 +563,10 @@
       <value>1024</value>
     </param>
     <param>
+      <key>freqhalf</key>
+      <value>True</value>
+    </param>
+    <param>
       <key>wintype</key>
       <value>firdes.WIN_BLACKMAN_hARRIS</value>
     </param>
@@ -495,6 +615,22 @@
       <value>True</value>
     </param>
     <param>
+      <key>tr_mode</key>
+      <value>qtgui.TRIG_MODE_FREE</value>
+    </param>
+    <param>
+      <key>tr_level</key>
+      <value>0.0</value>
+    </param>
+    <param>
+      <key>tr_chan</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>tr_tag</key>
+      <value>""</value>
+    </param>
+    <param>
       <key>label1</key>
       <value></value>
     </param>
@@ -1367,30 +1503,65 @@
     </param>
   </block>
   <block>
-    <key>gsm_receiver</key>
+    <key>gsm_input</key>
     <param>
       <key>id</key>
-      <value>gsm_receiver_0</value>
+      <value>gsm_input_0</value>
     </param>
     <param>
       <key>_enabled</key>
       <value>True</value>
     </param>
     <param>
+      <key>ppm</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>fc</key>
+      <value>fc</value>
+    </param>
+    <param>
       <key>osr</key>
       <value>4</value>
     </param>
     <param>
-      <key>cell_allocation</key>
-      <value>[0]</value>
+      <key>samp_rate_in</key>
+      <value>samp_rate</value>
     </param>
     <param>
-      <key>tseq_nums</key>
-      <value>[]</value>
+      <key>alias</key>
+      <value></value>
     </param>
     <param>
-      <key>num_streams</key>
-      <value>1</value>
+      <key>affinity</key>
+      <value></value>
+    </param>
+    <param>
+      <key>minoutbuf</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>maxoutbuf</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(253, 289)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>gsm_control_channels_decoder</key>
+    <param>
+      <key>id</key>
+      <value>gsm_control_channels_decoder_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
     </param>
     <param>
       <key>alias</key>
@@ -1410,7 +1581,7 @@
     </param>
     <param>
       <key>_coordinate</key>
-      <value>(434, 272)</value>
+      <value>(916, 272)</value>
     </param>
     <param>
       <key>_rotation</key>
@@ -1418,30 +1589,73 @@
     </param>
   </block>
   <block>
-    <key>gsm_input</key>
+    <key>gsm_universal_ctrl_chans_demapper</key>
     <param>
       <key>id</key>
-      <value>gsm_input_0</value>
+      <value>gsm_universal_ctrl_chans_demapper_0</value>
     </param>
     <param>
       <key>_enabled</key>
       <value>True</value>
     </param>
     <param>
-      <key>ppm</key>
+      <key>starts_fn_mod51</key>
+      <value>[2,6,12,16,22,26,32,36,42,46]</value>
+    </param>
+    <param>
+      <key>channel_types</key>
+      <value>[BCCH,CCCH,CCCH,CCCH,CCCH,CCCH,CCCH,CCCH,CCCH,CCCH]</value>
+    </param>
+    <param>
+      <key>alias</key>
+      <value></value>
+    </param>
+    <param>
+      <key>affinity</key>
+      <value></value>
+    </param>
+    <param>
+      <key>minoutbuf</key>
       <value>0</value>
     </param>
     <param>
-      <key>fc</key>
-      <value>fc</value>
+      <key>maxoutbuf</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(648, 272)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>gsm_receiver</key>
+    <param>
+      <key>id</key>
+      <value>gsm_receiver_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
     </param>
     <param>
       <key>osr</key>
       <value>4</value>
     </param>
     <param>
-      <key>samp_rate_in</key>
-      <value>samp_rate</value>
+      <key>cell_allocation</key>
+      <value>[0]</value>
+    </param>
+    <param>
+      <key>tseq_nums</key>
+      <value>[]</value>
+    </param>
+    <param>
+      <key>num_streams</key>
+      <value>1</value>
     </param>
     <param>
       <key>alias</key>
@@ -1461,7 +1675,7 @@
     </param>
     <param>
       <key>_coordinate</key>
-      <value>(253, 289)</value>
+      <value>(434, 272)</value>
     </param>
     <param>
       <key>_rotation</key>
@@ -1475,12 +1689,6 @@
     <sink_key>0</sink_key>
   </connection>
   <connection>
-    <source_block_id>gsm_get_bcch_or_ccch_bursts_0</source_block_id>
-    <sink_block_id>gsm_control_channels_decoder_0</sink_block_id>
-    <source_key>bursts</source_key>
-    <sink_key>bursts</sink_key>
-  </connection>
-  <connection>
     <source_block_id>gsm_control_channels_decoder_0</source_block_id>
     <sink_block_id>gsm_message_printer_0</sink_block_id>
     <source_key>msgs</source_key>
@@ -1493,12 +1701,6 @@
     <sink_key>pdus</sink_key>
   </connection>
   <connection>
-    <source_block_id>gsm_receiver_0</source_block_id>
-    <sink_block_id>gsm_get_bcch_or_ccch_bursts_0</sink_block_id>
-    <source_key>C0</source_key>
-    <sink_key>bursts</sink_key>
-  </connection>
-  <connection>
     <source_block_id>uhd_usrp_source_0</source_block_id>
     <sink_block_id>gsm_input_0</sink_block_id>
     <source_key>0</source_key>
@@ -1510,4 +1712,16 @@
     <source_key>0</source_key>
     <sink_key>0</sink_key>
   </connection>
+  <connection>
+    <source_block_id>gsm_universal_ctrl_chans_demapper_0</source_block_id>
+    <sink_block_id>gsm_control_channels_decoder_0</sink_block_id>
+    <source_key>bursts</source_key>
+    <sink_key>bursts</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>gsm_receiver_0</source_block_id>
+    <sink_block_id>gsm_universal_ctrl_chans_demapper_0</sink_block_id>
+    <source_key>C0</source_key>
+    <sink_key>bursts</sink_key>
+  </connection>
 </flow_graph>
diff --git a/grc/CMakeLists.txt b/grc/CMakeLists.txt
index ef06807..d1628cc 100644
--- a/grc/CMakeLists.txt
+++ b/grc/CMakeLists.txt
@@ -25,6 +25,7 @@ install(FILES
     receiver/gsm_sch_detector.xml
     receiver/gsm_fcch_detector.xml
     demapping/gsm_get_bcch_or_ccch_bursts.xml
+    demapping/gsm_universal_ctrl_chans_demapper.xml 
     decoding/gsm_control_channels_decoder.xml
     misc_utils/gsm_extract_system_info.xml
     misc_utils/gsm_controlled_rotator_cc.xml
diff --git a/grc/demapping/gsm_universal_ctrl_chans_demapper.xml b/grc/demapping/gsm_universal_ctrl_chans_demapper.xml
new file mode 100644
index 0000000..48b0f83
--- /dev/null
+++ b/grc/demapping/gsm_universal_ctrl_chans_demapper.xml
@@ -0,0 +1,32 @@
+<?xml version="1.0"?>
+<block>
+  <name>Universal ctrl chans demapper</name>
+  <key>gsm_universal_ctrl_chans_demapper</key>
+  <import>import gsm</import>
+  <make>gsm.universal_ctrl_chans_demapper($starts_fn_mod51, $channel_types)</make>
+
+  <param>
+    <name>starts_fn_mod51</name>
+    <key>starts_fn_mod51</key>
+    <value>[2,6,12,16,22,26,32,36,42,46]</value>
+    <type>int_vector</type>
+    <hide>part</hide>
+  </param>
+
+  <param>
+    <name>channel_types</name>
+    <key>channel_types</key>
+    <value>[1,2,2,2,2,2,2,2,2,2]</value>
+    <type>int_vector</type>
+    <hide>part</hide>
+  </param>
+
+  <sink>
+    <name>bursts</name>
+    <type>message</type>
+  </sink>
+  <source>
+    <name>bursts</name>
+    <type>message</type>
+  </source>
+</block>
diff --git a/grc/gsm_block_tree.xml b/grc/gsm_block_tree.xml
index 789932a..df463b2 100644
--- a/grc/gsm_block_tree.xml
+++ b/grc/gsm_block_tree.xml
@@ -22,6 +22,7 @@
     <cat>
       <name>Logical channels demapping</name>
       <block>gsm_get_bcch_or_ccch_bursts</block>
+      <block>gsm_universal_ctrl_chans_demapper</block>
     </cat>
     <cat>
       <name>Decoding</name>
diff --git a/include/gsm/demapping/CMakeLists.txt b/include/gsm/demapping/CMakeLists.txt
index bbbbc21..11fa6e5 100644
--- a/include/gsm/demapping/CMakeLists.txt
+++ b/include/gsm/demapping/CMakeLists.txt
@@ -21,5 +21,6 @@
 # Install public header files
 ########################################################################
 install(FILES
+    universal_ctrl_chans_demapper.h
     get_bcch_or_ccch_bursts.h DESTINATION include/gsm/demapping
 )
diff --git a/include/gsm/demapping/universal_ctrl_chans_demapper.h b/include/gsm/demapping/universal_ctrl_chans_demapper.h
new file mode 100644
index 0000000..8e8abb5
--- /dev/null
+++ b/include/gsm/demapping/universal_ctrl_chans_demapper.h
@@ -0,0 +1,56 @@
+/* -*- c++ -*- */
+/* 
+ * Copyright 2014 <+YOU OR YOUR COMPANY+>.
+ * 
+ * This 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.
+ * 
+ * This software 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 this software; see the file COPYING.  If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street,
+ * Boston, MA 02110-1301, USA.
+ */
+
+
+#ifndef INCLUDED_GSM_UNIVERSAL_CTRL_CHANS_DEMAPPER_H
+#define INCLUDED_GSM_UNIVERSAL_CTRL_CHANS_DEMAPPER_H
+
+#include <gsm/api.h>
+#include <gnuradio/block.h>
+
+namespace gr {
+  namespace gsm {
+
+    /*!
+     * \brief <+description of block+>
+     * \ingroup gsm
+     *
+     */
+    class GSM_API universal_ctrl_chans_demapper : virtual public gr::block
+    {
+     public:
+      typedef boost::shared_ptr<universal_ctrl_chans_demapper> sptr;
+
+      /*!
+       * \brief Return a shared_ptr to a new instance of gsm::universal_ctrl_chans_demapper.
+       *
+       * To avoid accidental use of raw pointers, gsm::universal_ctrl_chans_demapper's
+       * constructor is in a private implementation
+       * class. gsm::universal_ctrl_chans_demapper::make is the public interface for
+       * creating new instances.
+       */
+      static sptr make(const std::vector<int> &starts_fn_mod51, const std::vector<int> &channel_types);
+    };
+
+  } // namespace gsm
+} // namespace gr
+
+#endif /* INCLUDED_GSM_UNIVERSAL_CTRL_CHANS_DEMAPPER_H */
+
diff --git a/lib/CMakeLists.txt b/lib/CMakeLists.txt
index e4ed842..f420820 100644
--- a/lib/CMakeLists.txt
+++ b/lib/CMakeLists.txt
@@ -31,6 +31,7 @@ list(APPEND gsm_sources
     receiver/sch.c
     misc_utils/bursts_printer_impl.cc
     misc_utils/extract_system_info_impl.cc
+    demapping/universal_ctrl_chans_demapper_impl.cc
     demapping/get_bcch_or_ccch_bursts_impl.cc
     decoding/control_channels_decoder_impl.cc
     decoding/cch.c
diff --git a/lib/demapping/universal_ctrl_chans_demapper_impl.cc b/lib/demapping/universal_ctrl_chans_demapper_impl.cc
new file mode 100644
index 0000000..ea9a06e
--- /dev/null
+++ b/lib/demapping/universal_ctrl_chans_demapper_impl.cc
@@ -0,0 +1,135 @@
+/* -*- c++ -*- */
+/* 
+ * Copyright 2014 <+YOU OR YOUR COMPANY+>.
+ * 
+ * This 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.
+ * 
+ * This software 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 this software; see the file COPYING.  If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <gnuradio/io_signature.h>
+#include "universal_ctrl_chans_demapper_impl.h"
+#include <gsm/gsmtap.h>
+
+namespace gr {
+  namespace gsm {
+
+    universal_ctrl_chans_demapper::sptr
+    universal_ctrl_chans_demapper::make(const std::vector<int> &starts_fn_mod51, const std::vector<int> &channel_types)
+    {
+      return gnuradio::get_initial_sptr
+        (new universal_ctrl_chans_demapper_impl(starts_fn_mod51, channel_types));
+    }
+
+    /*
+     * The private constructor
+     */
+    universal_ctrl_chans_demapper_impl::universal_ctrl_chans_demapper_impl(const std::vector<int> &starts_fn_mod51, const std::vector<int> &channel_types)
+      : gr::block("universal_ctrl_chans_demapper",
+              gr::io_signature::make(0, 0, 0),
+              gr::io_signature::make(0, 0, 0))
+    {
+    
+        d_timeslot=0;
+        for(int ii=0; ii<51; ii++)
+        {
+            d_starts_fn_mod51[ii]=0;
+            d_channel_types[ii]=0;
+        }
+        
+        std::vector<int>::const_iterator s;
+        std::vector<int>::const_iterator ch_type;
+        
+        for(s=starts_fn_mod51.begin(), ch_type=channel_types.begin();s != starts_fn_mod51.end(); s++)
+        {
+            if((*s > 0) and (*s < (51-4)))
+            {
+                for(int ii=0; ii<4; ii++){
+                    d_starts_fn_mod51[*s+ii] = *s;
+                    if(ch_type!=channel_types.end())
+                    {
+                        d_channel_types[*s+ii] = *ch_type;
+                    }
+                }
+                if(ch_type!=channel_types.end())
+                {
+                    ch_type++;
+                }
+            }
+        }
+        
+        
+        message_port_register_in(pmt::mp("bursts"));
+        set_msg_handler(pmt::mp("bursts"), boost::bind(&universal_ctrl_chans_demapper_impl::filter_ctrl_chans, this, _1));
+        message_port_register_out(pmt::mp("bursts"));
+    }
+
+    /*
+     * Our virtual destructor.
+     */
+    universal_ctrl_chans_demapper_impl::~universal_ctrl_chans_demapper_impl()
+    {
+    }
+    
+    void universal_ctrl_chans_demapper_impl::filter_ctrl_chans(pmt::pmt_t msg)
+    {
+        pmt::pmt_t header_blob = pmt::car(msg);
+        pmt::pmt_t content = pmt::cdr(msg);
+        gsmtap_hdr * header = (gsmtap_hdr *)pmt::blob_data(header_blob);
+        uint32_t frame_nr = be32toh(header->frame_number);
+
+        uint32_t fn_mod51 = frame_nr % 51;
+        uint32_t fn51_start = d_starts_fn_mod51[fn_mod51];
+        uint32_t fn51_stop = fn51_start + 3;
+        uint32_t ch_type = d_channel_types[fn_mod51];
+        header->sub_type = ch_type;
+
+        if(header->timeslot==d_timeslot){
+            if(fn_mod51>=fn51_start && fn_mod51<=fn51_stop)
+            {
+                uint32_t ii = fn_mod51 - fn51_start;
+                d_frame_numbers[ii] = frame_nr;
+                d_bursts[ii] = msg;
+            }
+            
+            if(fn_mod51==fn51_stop)
+            {
+                //check for a situation where some bursts were lost
+                //in this situation frame numbers won't be consecutive
+                bool frames_are_consecutive = true;
+                for(int jj=1; jj<4; jj++)
+                {
+                    if((d_frame_numbers[jj]-d_frame_numbers[jj-1])!=1)
+                    {
+                        frames_are_consecutive = false;
+                    }
+                }
+                if(frames_are_consecutive)
+                {
+                    //send bursts to the output
+                    for(int jj=0; jj<4; jj++)
+                    {
+                        message_port_pub(pmt::mp("bursts"), d_bursts[jj]);
+                    }
+                } 
+            }
+        }
+    }
+  } /* namespace gsm */
+} /* namespace gr */
+
diff --git a/lib/demapping/universal_ctrl_chans_demapper_impl.h b/lib/demapping/universal_ctrl_chans_demapper_impl.h
new file mode 100644
index 0000000..472b321
--- /dev/null
+++ b/lib/demapping/universal_ctrl_chans_demapper_impl.h
@@ -0,0 +1,48 @@
+/* -*- c++ -*- */
+/* 
+ * Copyright 2014 <+YOU OR YOUR COMPANY+>.
+ * 
+ * This 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.
+ * 
+ * This software 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 this software; see the file COPYING.  If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#ifndef INCLUDED_GSM_UNIVERSAL_CTRL_CHANS_DEMAPPER_IMPL_H
+#define INCLUDED_GSM_UNIVERSAL_CTRL_CHANS_DEMAPPER_IMPL_H
+
+#include <gsm/demapping/universal_ctrl_chans_demapper.h>
+
+namespace gr {
+  namespace gsm {
+
+    class universal_ctrl_chans_demapper_impl : public universal_ctrl_chans_demapper
+    {
+     private:
+      unsigned int d_starts_fn_mod51[51];
+      unsigned int d_channel_types[51];
+      unsigned int d_timeslot;
+      uint32_t d_frame_numbers[4];
+      pmt::pmt_t d_bursts[4];
+     public:
+      universal_ctrl_chans_demapper_impl(const std::vector<int> &starts_fn_mod51, const std::vector<int> &channel_types);
+      ~universal_ctrl_chans_demapper_impl();
+
+      void filter_ctrl_chans(pmt::pmt_t msg);
+    };
+
+  } // namespace gsm
+} // namespace gr
+
+#endif /* INCLUDED_GSM_UNIVERSAL_CTRL_CHANS_DEMAPPER_IMPL_H */
+
diff --git a/swig/gsm_swig.i b/swig/gsm_swig.i
index 41acaf6..5f3dcb7 100644
--- a/swig/gsm_swig.i
+++ b/swig/gsm_swig.i
@@ -10,6 +10,7 @@
 %{
 #include "gsm/receiver/receiver.h"
 #include "gsm/demapping/get_bcch_or_ccch_bursts.h"
+#include "gsm/demapping/universal_ctrl_chans_demapper.h"
 #include "gsm/decoding/control_channels_decoder.h"
 #include "gsm/misc_utils/bursts_printer.h"
 #include "gsm/misc_utils/controlled_const_source_f.h"
@@ -27,6 +28,8 @@ GR_SWIG_BLOCK_MAGIC2(gsm, control_channels_decoder);
 
 %include "gsm/demapping/get_bcch_or_ccch_bursts.h"
 GR_SWIG_BLOCK_MAGIC2(gsm, get_bcch_or_ccch_bursts);
+%include "gsm/demapping/universal_ctrl_chans_demapper.h"
+GR_SWIG_BLOCK_MAGIC2(gsm, universal_ctrl_chans_demapper);
 
 %include "gsm/misc_utils/bursts_printer.h"
 GR_SWIG_BLOCK_MAGIC2(gsm, bursts_printer);