1 files changed, 136 insertions, 0 deletions
diff --git a/gr-fec/lib/ldpc_R_U_encoder_impl.cc b/gr-fec/lib/ldpc_R_U_encoder_impl.cc
new file mode 100644
index 0000000000..7da8e12094
--- /dev/null
+++ b/gr-fec/lib/ldpc_R_U_encoder_impl.cc
@@ -0,0 +1,136 @@
+/* -*- c++ -*- */
+/* 
+ * Copyright 2013-2014 Free Software Foundation, Inc.
+ * 
+ * This 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.
+ * 
+ * This software 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 this software; 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 <ldpc_R_U_encoder_impl.h>
+#include <sstream>
+
+namespace gr {
+  namespace fec {
+    namespace code {
+      generic_encoder::sptr
+      ldpc_R_U_encoder::make(ldpc_par_chk_mtrx *H_obj)
+      {
+        return generic_encoder::sptr
+          (new ldpc_R_U_encoder_impl(H_obj));
+      }
+
+      ldpc_R_U_encoder_impl::ldpc_R_U_encoder_impl(ldpc_par_chk_mtrx *H_obj) 
+        : generic_encoder("ldpc_R_U_encoder")
+      {
+        // LDPC parity check matrix to use for encoding
+        d_H = H_obj;
+        // Set frame size to k, the # of bits in the information word
+        // All buffers and settings will be based on this value.
+        set_frame_size(d_H->k());
+      }
+
+      ldpc_R_U_encoder_impl::~ldpc_R_U_encoder_impl()
+      {
+      }
+
+      int
+      ldpc_R_U_encoder_impl::get_output_size()
+      {
+        return d_H->n();
+      }
+
+      int
+      ldpc_R_U_encoder_impl::get_input_size()
+      {
+        return d_frame_size;
+      }
+
+      bool
+      ldpc_R_U_encoder_impl::set_frame_size(unsigned int frame_size)
+      {
+        bool ret = true;
+        // TODO add some bounds check here? The frame size is
+        // constant and specified by the size of the parity check
+        // matrix used for encoding.
+        d_frame_size = frame_size;
+
+        return ret;        
+      }
+
+      double
+      ldpc_R_U_encoder_impl::rate()
+      {
+        return (d_H->n())/static_cast<double>(d_frame_size);
+      }
+
+      void
+      ldpc_R_U_encoder_impl::generic_work(void *inbuffer,
+                                          void *outbuffer)
+      {
+        // Populate the information word
+        const unsigned char *in = (const unsigned char *)inbuffer;
+        unsigned int index, k = d_H->k();
+        gsl_matrix *s = gsl_matrix_alloc(k, 1);
+        for (index = 0; index < k; index++) {
+          double value = static_cast<double>(in[index]);
+          gsl_matrix_set(s, index, 0, value);
+        }
+
+        // Solve for p2 (parity part)
+        const gsl_matrix *A     = d_H->A();
+        const gsl_matrix *B     = d_H->B();
+        const gsl_matrix *D     = d_H->D();
+        const gsl_matrix *E     = d_H->E();
+        const gsl_matrix *inv_T = d_H->T_inverse();
+        const gsl_matrix *inv_p = d_H->phi_inverse();
+        const gsl_matrix *temp1 = d_H->mult_matrices_mod2(B, s);
+        const gsl_matrix *temp2 = d_H->mult_matrices_mod2(inv_T,
+                                                          temp1);
+        const gsl_matrix *temp3 = d_H->mult_matrices_mod2(E, temp2);
+        const gsl_matrix *temp4 = d_H->mult_matrices_mod2(D, s);
+        const gsl_matrix *temp5 = d_H->add_matrices_mod2(temp4,
+                                                         temp3);
+        const gsl_matrix *p2 = d_H->mult_matrices_mod2(inv_p, temp5);
+
+        // Solve for p1 (parity part)
+        const gsl_matrix *temp6 = d_H->mult_matrices_mod2(A, p2);
+        const gsl_matrix *temp7 = d_H->add_matrices_mod2(temp6,
+                                                         temp1);
+        const gsl_matrix *p1 = d_H->mult_matrices_mod2(inv_T, temp7);
+
+        // Populate the codeword to be output
+        unsigned int p1_length = (*p1).size1;
+        unsigned int p2_length = (*p2).size1;
+        unsigned char *out = (unsigned char*)outbuffer;
+        for (index = 0; index < p1_length; index++) {
+          int value = gsl_matrix_get(p1, index, 0);
+          out[index] = value;
+        }
+        for (index = 0; index < p2_length; index++) {
+          int value = gsl_matrix_get(p2, index, 0);
+          out[p1_length+index] = value;
+        }
+        for (index = 0; index < k; index++) {
+          int value = gsl_matrix_get(s, index, 0);
+          out[p1_length+p2_length+index] = value;
+        }
+      }
+    } /* namespace code */
+  } /* namespace fec */
+} /* namespace gr */
+\ No newline at end of file