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diff --git a/gr-digital/lib/kurtotic_equalizer_cc_impl.h b/gr-digital/lib/kurtotic_equalizer_cc_impl.h
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+/* -*- c++ -*- */
+/*
+ * Copyright 2011,2012 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_KURTOTIC_EQUALIZER_CC_IMPL_H
+#define	INCLUDED_DIGITAL_KURTOTIC_EQUALIZER_CC_IMPL_H
+
+#include <digital/kurtotic_equalizer_cc.h>
+#include <filter/fir_filter.h>
+#include <gr_math.h>
+#include <stdexcept>
+
+namespace gr {
+  namespace digital {
+
+    class kurtotic_equalizer_cc_impl
+      : public kurtotic_equalizer_cc, filter::kernel::fir_filter_ccc
+    {
+    private:
+      std::vector<gr_complex> d_new_taps;
+      bool d_updated;
+      gr_complex d_error;
+
+      float d_mu;
+      float d_p, d_m;
+      gr_complex d_q, d_u;
+      float d_alpha_p, d_alpha_q, d_alpha_m;
+
+      gr_complex sign(gr_complex x)
+      {
+	float re = (float)(x.real() >= 0.0f);
+	float im = (float)(x.imag() >= 0.0f);
+	return gr_complex(re, im);
+      }
+
+    protected:
+      virtual gr_complex error(const gr_complex &out) 
+      {
+	// p = E[|z|^2]
+	// q = E[z^2]
+	// m = E[|z|^4]
+	// u = E[kurtosis(z)]
+
+	float nrm = norm(out);
+	gr_complex cnj = conj(out);
+	float epsilon_f = 1e-12;
+	gr_complex epsilon_c = gr_complex(1e-12, 1e-12);
+    
+	d_p = (1-d_alpha_p)*d_p + (d_alpha_p)*nrm + epsilon_f;
+	d_q = (1-d_alpha_q)*d_q + (d_alpha_q)*out*out + epsilon_c;
+	d_m = (1-d_alpha_m)*d_m + (d_alpha_m)*nrm*nrm + epsilon_f;
+	d_u = d_m - 2.0f*(d_p*d_p) - d_q*d_q;
+
+	gr_complex F = (1.0f / (d_p*d_p*d_p)) *
+	  (sign(d_u) * (nrm*cnj - 2.0f*d_p*cnj - conj(d_q)*out) -
+	   abs(d_u)*cnj);
+
+	float re = gr_clip(F.real(), 1.0);
+	float im = gr_clip(F.imag(), 1.0);
+	return gr_complex(re, im);
+      }
+
+      virtual void update_tap(gr_complex &tap, const gr_complex &in) 
+      {
+	tap += d_mu*in*d_error;
+      }
+  
+    public:
+      kurtotic_equalizer_cc_impl(int num_taps, float mu);
+      ~kurtotic_equalizer_cc_impl();
+
+      float gain() const { return d_mu; }
+
+      void set_gain(float mu) 
+      {
+	if(mu < 0)
+	  throw std::out_of_range("kurtotic_equalizer_cc_impl::set_gain: Gain value must be >= 0");
+	d_mu = mu;
+      }
+
+      int work(int noutput_items,
+	       gr_vector_const_void_star &input_items,
+	       gr_vector_void_star &output_items);
+    };
+
+  } /* namespace digital */
+} /* namespace gr */
+
+#endif /* INCLUDED_DIGITAL_KURTOTIC_EQUALIZER_CC_IMPL_H */
+