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diff --git a/gr-blocks/include/blocks/plateau_detector_fb.h b/gr-blocks/include/blocks/plateau_detector_fb.h
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+/* -*- c++ -*- */
+/*
+ * Copyright 2012-2013 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_BLOCKS_PLATEAU_DETECTOR_FB_H
+#define INCLUDED_BLOCKS_PLATEAU_DETECTOR_FB_H
+
+#include <blocks/api.h>
+#include <gr_sync_block.h>
+
+namespace gr {
+  namespace blocks {
+
+    /*!
+     * \brief Detects a plateau and marks the middle.
+     * \ingroup peak_detectors_blk
+     *
+     * \details
+     * Detect a plateau of a-priori known height. Input is a stream of floats,
+     * the output is a stream of bytes. Whenever a plateau is detected, the
+     * middle of that plateau is marked with a '1' on the output stream (all
+     * other samples are left at zero).
+     *
+     * You can use this in a Schmidl & Cox synchronisation algorithm to interpret
+     * the output of the normalized correlator. Just pass the length of the cyclic
+     * prefix (in samples) as the max_len parameter).
+     *
+     * Unlike the peak detectors, you must the now the absolute height of the plateau.
+     * Whenever the amplitude exceeds the given threshold, it starts assuming the
+     * presence of a plateau.
+     *
+     * An implicit hysteresis is provided by the fact that after detecting one plateau,
+     * it waits at least max_len samples before the next plateau can be detected.
+     */
+    class BLOCKS_API plateau_detector_fb : virtual public gr_sync_block
+    {
+    public:
+       typedef boost::shared_ptr<plateau_detector_fb> sptr;
+
+       /*!
+	* \param max_len Maximum length of the plateau
+	* \param threshold Anything above this value is considered a plateau
+	*/
+       static sptr make(int max_len, float threshold=0.9);
+    };
+
+  } // namespace blocks
+} // namespace gr
+
+#endif /* INCLUDED_BLOCKS_PLATEAU_DETECTOR_FB_H */
+