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diff --git a/gr-digital/include/digital_mpsk_snr_est_cc.h b/gr-digital/include/digital_mpsk_snr_est_cc.h
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+/* -*- c++ -*- */
+/*
+ * Copyright 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.
+ */
+#ifndef INCLUDED_DIGITAL_MPSK_SNR_EST_CC_H
+#define INCLUDED_DIGITAL_MPSK_SNR_EST_CC_H
+
+#include <digital_api.h>
+#include <gr_sync_block.h>
+#include <digital_impl_mpsk_snr_est.h>
+
+class digital_mpsk_snr_est_cc;
+typedef boost::shared_ptr<digital_mpsk_snr_est_cc> digital_mpsk_snr_est_cc_sptr;
+
+DIGITAL_API digital_mpsk_snr_est_cc_sptr
+digital_make_mpsk_snr_est_cc(snr_est_type_t type,
+			     int tag_nsamples=10000,
+			     double alpha=0.001);
+
+//! \brief A block for computing SNR of a signal.
+/*! \ingroup snr_blk
+ *
+ *  This block can be used to monitor and retrieve estimations of the
+ *  signal SNR. It is designed to work in a flowgraph and passes all
+ *  incoming data along to its output.
+ *
+ *  The block is designed for use with M-PSK signals especially. The
+ *  type of estimator is specified as the \p type parameter in the
+ *  constructor. The estimators tend to trade off performance for
+ *  accuracy, although experimentation should be done to figure out
+ *  the right approach for a given implementation. Further, the
+ *  current set of estimators are designed and proven theoretically
+ *  under AWGN conditions; some amount of error should be assumed
+ *  and/or estimated for real channel conditions.
+ */
+class DIGITAL_API digital_mpsk_snr_est_cc : public gr_sync_block
+{
+ private:
+  snr_est_type_t d_type;
+  int d_nsamples, d_count;
+  double d_alpha;
+  digital_impl_mpsk_snr_est *d_snr_est;
+
+  //d_key is the tag name, 'snr', d_me is the block name + unique ID
+  pmt::pmt_t d_key, d_me; 
+
+  /*! Factory function returning shared pointer of this class
+   *
+   *  Parameters:
+   *
+   *  \param type: the type of estimator to use \ref ref_snr_est_types
+   *  "snr_est_type_t" for details about the available types.
+   *  \param tag_nsamples: after this many samples, a tag containing
+   *  the SNR (key='snr') will be sent
+   *  \param alpha: the update rate of internal running average
+   *  calculations.
+   */
+  friend DIGITAL_API digital_mpsk_snr_est_cc_sptr
+    digital_make_mpsk_snr_est_cc(snr_est_type_t type,
+				 int tag_nsamples,
+				 double alpha);
+  
+  // Private constructor
+  digital_mpsk_snr_est_cc(snr_est_type_t type,
+			  int tag_nsamples,
+			  double alpha);
+
+public:
+
+  ~digital_mpsk_snr_est_cc();
+
+  int work (int noutput_items,
+	    gr_vector_const_void_star &input_items,
+	    gr_vector_void_star &output_items);
+
+  //! Return the estimated signal-to-noise ratio in decibels
+  double snr();
+
+  //! Return the type of estimator in use
+  snr_est_type_t type() const;
+
+  //! Return how many samples between SNR tags
+  int tag_nsample() const;
+
+  //! Get the running-average coefficient
+  double alpha() const;
+
+  //! Set type of estimator to use
+  void set_type(snr_est_type_t t);
+
+  //! Set the number of samples between SNR tags
+  void set_tag_nsample(int n);
+
+  //! Set the running-average coefficient
+  void set_alpha(double alpha);
+};
+
+#endif /* INCLUDED_DIGITAL_MPSK_SNR_EST_CC_H */