Imported Upstream version 3.2.2

[debian/gnuradio] / gnuradio-core / src / lib / filter / gr_fractional_interpolator_cc.cc

diff --git a/gnuradio-core/src/lib/filter/gr_fractional_interpolator_cc.cc b/gnuradio-core/src/lib/filter/gr_fractional_interpolator_cc.cc
new file mode 100644 (file)
index 0000000..56a1a31
--- /dev/null
+++ b/gnuradio-core/src/lib/filter/gr_fractional_interpolator_cc.cc
@@ -0,0 +1,93 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2004,2007 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.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <gr_io_signature.h>
+#include <gr_fractional_interpolator_cc.h>
+#include <gri_mmse_fir_interpolator_cc.h>
+#include <stdexcept>
+
+// Public constructor
+gr_fractional_interpolator_cc_sptr gr_make_fractional_interpolator_cc(float phase_shift, float interp_ratio)
+{
+  return gr_fractional_interpolator_cc_sptr(new gr_fractional_interpolator_cc(phase_shift, interp_ratio));
+}
+
+gr_fractional_interpolator_cc::gr_fractional_interpolator_cc(float phase_shift, float interp_ratio)
+  : gr_block ("fractional_interpolator_cc",
+             gr_make_io_signature (1, 1, sizeof (gr_complex)),
+             gr_make_io_signature (1, 1, sizeof (gr_complex))),
+    d_mu (phase_shift), d_mu_inc (interp_ratio), d_interp(new gri_mmse_fir_interpolator_cc())
+{
+  if (interp_ratio <=  0)
+    throw std::out_of_range ("interpolation ratio must be > 0");
+  if (phase_shift <  0  || phase_shift > 1)
+    throw std::out_of_range ("phase shift ratio must be > 0 and < 1");
+
+  set_relative_rate (1.0 / interp_ratio);
+}
+
+gr_fractional_interpolator_cc::~gr_fractional_interpolator_cc()
+{
+  delete d_interp;
+}
+
+void
+gr_fractional_interpolator_cc::forecast(int noutput_items, gr_vector_int &ninput_items_required)
+{
+  unsigned ninputs = ninput_items_required.size();
+  for (unsigned i=0; i < ninputs; i++)
+
+    ninput_items_required[i] =
+      (int) ceil((noutput_items * d_mu_inc) + d_interp->ntaps());
+}
+
+int
+gr_fractional_interpolator_cc::general_work(int noutput_items,
+                                           gr_vector_int &ninput_items,
+                                           gr_vector_const_void_star &input_items,
+                                           gr_vector_void_star &output_items)
+{
+  const gr_complex *in = (const gr_complex *) input_items[0];
+  gr_complex *out = (gr_complex *) output_items[0];
+
+  int  ii = 0;                         // input index
+  int          oo = 0;                         // output index
+
+  while (oo < noutput_items) {
+
+    out[oo++] = d_interp->interpolate(&in[ii], d_mu);
+
+    double s = d_mu + d_mu_inc;
+    double f = floor (s);
+    int incr = (int) f;
+    d_mu = s - f;
+    ii += incr;
+  }
+
+  consume_each (ii);
+
+  return noutput_items;
+}