1 files changed, 123 insertions, 0 deletions
diff --git a/gr-fec/lib/polar_decoder_sc_list.cc b/gr-fec/lib/polar_decoder_sc_list.cc
new file mode 100644
index 0000000000..903b9413da
--- /dev/null
+++ b/gr-fec/lib/polar_decoder_sc_list.cc
@@ -0,0 +1,123 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2015 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 <gnuradio/io_signature.h>
+#include <gnuradio/fec/polar_decoder_sc_list.h>
+#include <volk/volk.h>
+#include <scl_list.h>
+
+#include <cmath>
+#include <algorithm>
+
+namespace gr {
+  namespace fec {
+    namespace code {
+
+      generic_decoder::sptr
+      polar_decoder_sc_list::make(int max_list_size, int block_size, int num_info_bits,
+                                  std::vector<int> frozen_bit_positions,
+                                  std::vector<char> frozen_bit_values)
+      {
+        return generic_decoder::sptr
+          (new polar_decoder_sc_list(max_list_size, block_size, num_info_bits,
+                                     frozen_bit_positions,
+                                     frozen_bit_values));
+      }
+
+      polar_decoder_sc_list::polar_decoder_sc_list(int max_list_size, int block_size,
+                                                   int num_info_bits,
+                                                   std::vector<int> frozen_bit_positions,
+                                                   std::vector<char> frozen_bit_values)
+        : polar_decoder_common(block_size, num_info_bits, frozen_bit_positions, frozen_bit_values)
+      {
+        d_scl = new polar::scl_list(max_list_size, block_size, block_power());
+      }
+
+      polar_decoder_sc_list::~polar_decoder_sc_list()
+      {
+        delete d_scl;
+      }
+
+      void
+      polar_decoder_sc_list::generic_work(void* in_buffer, void* out_buffer)
+      {
+        const float *in = (const float*) in_buffer;
+        unsigned char *out = (unsigned char*) out_buffer;
+
+        initialize_list(in);
+        const unsigned char* temp = decode_list();
+        extract_info_bits(out, temp);
+      }
+
+      void
+      polar_decoder_sc_list::initialize_list(const float* in_buf)
+      {
+        polar::path* init_path = d_scl->initial_path();
+        initialize_decoder(init_path->u_vec, init_path->llr_vec, in_buf);
+      }
+
+      const unsigned char*
+      polar_decoder_sc_list::decode_list()
+      {
+        for(int u_num = 0; u_num < block_size(); u_num++){
+          decode_bit(u_num);
+        }
+        return d_scl->optimal_path()->u_vec;
+      }
+
+      void
+      polar_decoder_sc_list::decode_bit(const int u_num)
+      {
+        calculate_llrs_for_list(u_num);
+        set_bit_in_list(u_num);
+      }
+
+      void
+      polar_decoder_sc_list::calculate_llrs_for_list(const int u_num)
+      {
+        for(unsigned int i = 0; i < d_scl->active_size(); i++){
+          polar::path* current_path = d_scl->next_active_path();
+          butterfly(current_path->llr_vec, current_path->u_vec, 0, u_num, u_num);
+        }
+      }
+
+      void
+      polar_decoder_sc_list::set_bit_in_list(const int u_num)
+      {
+        // 1. if frozen bit, update with known value
+        if(is_frozen_bit(u_num)){
+          const unsigned char frozen_bit = next_frozen_bit();
+          d_scl->set_frozen_bit(frozen_bit, u_num);
+        }
+        // 2. info bit
+        else{
+          d_scl->set_info_bit(u_num);
+        }
+      }
+
+    } /* namespace code */
+  } /* namespace fec */
+} /* namespace gr */