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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 2012 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>
+
+class digital_ofdm_sync_sc_cfb;
+typedef boost::shared_ptr<digital_ofdm_sync_sc_cfb> digital_ofdm_sync_sc_cfb_sptr;
+
+/*! \param fft_len FFT length
+ *  \param cp_len Length of the guard interval (cyclic prefix) in samples
+ */
+DIGITAL_API digital_ofdm_sync_sc_cfb_sptr
+digital_make_ofdm_sync_sc_cfb (int fft_len, int cp_len);
+
+/*!
+ * \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 digital_ofdm_sync_sc_cfb : public gr_hier_block2
+{
+ private:
+  friend DIGITAL_API digital_ofdm_sync_sc_cfb_sptr digital_make_ofdm_sync_sc_cfb (int fft_len, int cp_len);
+  digital_ofdm_sync_sc_cfb(int fft_len, int cp_len);
+
+ public:
+  ~digital_ofdm_sync_sc_cfb();
+
+};
+
+#endif /* INCLUDED_DIGITAL_OFDM_SYNC_SC_CFB_H */
+