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diff --git a/gr-fft/include/gnuradio/fft/fft_shift.h b/gr-fft/include/gnuradio/fft/fft_shift.h
new file mode 100644
index 0000000000..1ee08915b9
--- /dev/null
+++ b/gr-fft/include/gnuradio/fft/fft_shift.h
@@ -0,0 +1,82 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2019 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_FFT_FFT_SHIFT_H
+#define INCLUDED_FFT_FFT_SHIFT_H
+
+#include <algorithm>
+#include <cassert>
+#include <vector>
+
+namespace gr {
+namespace fft {
+
+  /*! \brief reorder FFT results which are ordered from 0 to 1 in normalized frequency
+   *  to -0.5 to 0.5 by cyclic shift
+   */
+  template<typename T>
+  class fft_shift {
+  public:
+    fft_shift(size_t fft_length)
+      : d_fftlen(fft_length)
+      , d_lenpos(fft_length/2 + (fft_length%2))
+      , d_lenneg(fft_length/2)
+      , d_buf(fft_length) {}
+
+    /*! performs the cyclic shift on a vector v
+     */
+    void shift(std::vector<T>& v) {
+      shift(&v.front(), v.size());
+    }
+
+    /*! performs the cyclic shift on an array
+     */
+    void shift(T* data, size_t fft_len) {
+      resize(fft_len);
+      std::copy_n(data,          d_lenpos, d_buf.begin());
+      std::copy_n(data+d_lenpos, d_lenneg, data);
+      std::copy_n(d_buf.begin(), d_lenpos, data+d_lenneg);
+    }
+
+    /*! if needed adjusts the buffer size to a new fft length
+     */
+    void resize(size_t fft_length) {
+      if (d_fftlen == fft_length)
+        return;
+      d_fftlen = fft_length;
+      d_lenpos = d_fftlen/2 + (d_fftlen%2);
+      d_lenneg = d_fftlen/2;
+      assert(d_lenpos + d_lenneg == d_fftlen);
+      d_buf.resize(d_lenpos);
+    }
+  protected:
+
+  private:
+    size_t d_fftlen;      // FFT length
+    size_t d_lenpos;      // number of FFT bins with positive frequencies
+    size_t d_lenneg;      // number of FFT bins with negative frequencies
+    std::vector<T> d_buf; // buffer used for cyclic shift
+  } ;
+
+} // namespace fft
+} // namespace gr
+#endif // INCLUDED_FFT_FFT_SHIFT_H