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diff --git a/gr-digital/include/digital/ofdm_sync_sc_cfb.h b/gr-digital/include/digital/ofdm_sync_sc_cfb.h
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+/* -*- c++ -*- */
+/* 
+ * Copyright 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_DIGITAL_OFDM_SYNC_SC_CFB_H
+#define INCLUDED_DIGITAL_OFDM_SYNC_SC_CFB_H
+
+#include <digital/api.h>
+#include <gr_hier_block2.h>
+
+namespace gr {
+  namespace digital {
+
+    /*!
+     * \brief Schmidl & Cox synchronisation for OFDM
+     * \ingroup ofdm_blk
+     * \ingroup sync_blk
+     *
+     * Input: complex samples.
+     * Output 0: Fine frequency offset, scaled by the OFDM symbol duration.
+     *           This is \f$\hat{\varphi}\f$ in [1]. The normalized frequency
+     *           offset is then 2.0*output0/fft_len.
+     * Output 1: Beginning of the first OFDM symbol after the first (doubled) OFDM
+     *           symbol. The beginning is marked with a 1 (it's 0 everywhere else).
+     *
+     * The evaluation of the coarse frequency offset is *not* done in this block.
+     * Also, the initial equalizer taps are not calculated here.
+     *
+     * Note that we use a different normalization factor in the timing metric than
+     * the authors do in their original work[1]. If the timing metric (8) is
+     * \f[
+     * M(d) = \frac{|P(d)|^2}{(R(d))^2},
+     * \f]
+     * we calculate the normalization as
+     * \f[
+     * R(d) = \frac{1}{2} \sum_{k=0}^{N-1} |r_{k+d}|^2,
+     * \f]
+     * i.e., we estimate the energy from *both* half-symbols. This avoids spurious detects
+     * at the end of a burst, when the energy level suddenly drops.
+     *
+     * [1] Schmidl, T.M. and Cox, D.C., "Robust frequency and timing synchronization for OFDM",
+     *     Communications, IEEE Transactions on, 1997.
+     */
+    class DIGITAL_API ofdm_sync_sc_cfb : virtual public gr_hier_block2
+    {
+     public:
+      typedef boost::shared_ptr<ofdm_sync_sc_cfb> sptr;
+
+      /*! \param fft_len FFT length
+       *  \param cp_len Length of the guard interval (cyclic prefix) in samples
+       */
+      static sptr make(int fft_len, int cp_len);
+    };
+
+  } // namespace digital
+} // namespace gr
+
+#endif /* INCLUDED_DIGITAL_OFDM_SYNC_SC_CFB_H */
+