Merge commit 'v3.3.0' into upstream

[debian/gnuradio] / gr-atsc / src / lib / atsci_root_raised_cosine.cc

diff --git a/gr-atsc/src/lib/atsci_root_raised_cosine.cc b/gr-atsc/src/lib/atsci_root_raised_cosine.cc
new file mode 100644 (file)
index 0000000..9409d2b
--- /dev/null
+++ b/gr-atsc/src/lib/atsci_root_raised_cosine.cc
@@ -0,0 +1,36 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2002 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.
+ */
+
+#include <atsc_consts.h>
+#include <atsci_root_raised_cosine.h>
+#include <gr_firdes.h>
+
+vector<float> 
+atsc_root_raised_cosine::taps (double sampling_rate)
+{
+  static const double symbol_rate = ATSC_SYMBOL_RATE/2;        // 1/2 as wide because we're designing lp filter
+  // static const int    NTAPS = 93;                   // good number
+  // static const int    NTAPS = 745;                  // better number
+  static const int    NTAPS = 279;                     // better number
+
+  return gr_firdes::root_raised_cosine (1.0, sampling_rate, symbol_rate, .115, NTAPS);
+}