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
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+++ 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 */
+