channels: new frequency selective fading block

author: Tim O'Shea <tim.oshea753@gmail.com> 2013-06-06 16:15:52 -0400
committer: Tim O'Shea <tim.oshea753@gmail.com> 2013-06-06 16:15:52 -0400
commit: 9896a6727bc1446e0597ad51cc4305acfb46ff1b (patch)
tree: ab6fcc2f599d65ef1c46e2f2e1a78cf67068985f
parent: 553c06df3dcc913219e6462131861a937acb8b5e (diff)
13 files changed, 644 insertions, 117 deletions
diff --git a/gr-channels/grc/CMakeLists.txt b/gr-channels/grc/CMakeLists.txt
index cbbf75901c..3bda29f01d 100644
--- a/gr-channels/grc/CMakeLists.txt
+++ b/gr-channels/grc/CMakeLists.txt
@@ -21,6 +21,7 @@ install(FILES
   channels_block_tree.xml
   channels_channel_model.xml
   channels_fading_model.xml
+  channels_selective_fading_model.xml
   DESTINATION ${GRC_BLOCKS_DIR}
   COMPONENT "channels_python"
 )
diff --git a/gr-channels/grc/channels_selective_fading_model.xml b/gr-channels/grc/channels_selective_fading_model.xml
new file mode 100644
index 0000000000..2d29a477ae
--- /dev/null
+++ b/gr-channels/grc/channels_selective_fading_model.xml
@@ -0,0 +1,95 @@
+<?xml version="1.0"?>
+<!--
+###################################################
+##Frequency Selective Fading Model
+###################################################
+ -->
+<block>
+	<name>Frequency Selective Fading Model</name>
+	<key>channels_selective_fading_model</key>
+	<import>from gnuradio import channels</import>
+	<make>channels.selective_fading_model( $N, $fDTs, $LOS, $K, $seed, $delays, $mags, $ntaps )</make>
+    <callback>set_fDTs($fDTs)</callback>
+    <callback>set_K($K)</callback>
+	<param>
+		<name>Num Sinusoids (SoS model)</name>
+		<key>N</key>
+		<value>8</value>
+		<type>int</type>
+	</param>
+	<param>
+		<name>Normalized Max Doppler (fD*Ts)</name>
+		<key>fDTs</key>
+		<value>10.0/samp_rate</value>
+		<type>real</type>
+	</param>
+	<param>
+		<name>LOS Model</name>
+		<key>LOS</key>
+        <type>enum</type>
+        <option>
+            <name>Rayleigh/NLOS</name>
+            <key>False</key>
+            <opt>hide_K:all</opt>
+        </option>
+        <option>
+            <name>Rician/LOS</name>
+            <key>True</key>
+            <opt>hide_K:</opt>
+        </option>
+	</param>
+	<param>
+		<name>Rician factor (K)</name>
+		<key>K</key>
+		<value>4.0</value>
+		<type>real</type>
+        <hide>$LOS.hide_K</hide>
+	</param>
+	<param>
+		<name>Seed</name>
+		<key>seed</key>
+		<value>0</value>
+		<type>int</type>
+	</param>
+    <param>
+        <name>PDP Delays (samp)</name>
+        <key>delays</key>
+        <value>3.1,3.25,3.78</value>
+        <type>float_vector</type>
+    </param>
+    <param>
+        <name>PDP Magnitudes</name>
+        <key>mags</key>
+        <value>1,0.99,0.97</value>
+        <type>float_vector</type>
+    </param>
+	<param>
+		<name>Num Taps</name>
+		<key>ntaps</key>
+		<value>8</value>
+		<type>int</type>
+	</param>
+	<sink>
+		<name>in</name>
+		<type>complex</type>
+	</sink>
+	<source>
+		<name>out</name>
+		<type>complex</type>
+	</source>
+    <doc>
+  This algorithm implements the method described in 
+   Compact Rayleigh and Rician fading simulator based on random walk processes
+   A. Alimohammad S.F. Fard B.F. Cockburn C. Schlegel
+   26th November 2008
+
+    int d_N=8;          // number of sinusoids
+    float d_fDTs=0.01   // normalized maximum doppler frequency (f_doppler / f_samprate)
+    float d_K=4;        // Rician factor (ratio of the specular power to the scattered power)
+    bool d_LOS=true;    // LOS path exists? chooses Rician (LOS) vs Rayleigh (NLOS) model.
+    int seed=0;         // noise seed
+
+    If using a LOS model, the first delay and mag should correspond with the LOS component
+
+    </doc>
+</block>
diff --git a/gr-channels/include/gnuradio/channels/CMakeLists.txt b/gr-channels/include/gnuradio/channels/CMakeLists.txt
index c0c70e2b00..f9a535b9c0 100644
--- a/gr-channels/include/gnuradio/channels/CMakeLists.txt
+++ b/gr-channels/include/gnuradio/channels/CMakeLists.txt
@@ -24,6 +24,7 @@ install(FILES
     api.h
     channel_model.h
     fading_model.h
+    selective_fading_model.h
     DESTINATION ${GR_INCLUDE_DIR}/gnuradio/channels
     COMPONENT "channels_devel"
 )
diff --git a/gr-channels/include/gnuradio/channels/selective_fading_model.h b/gr-channels/include/gnuradio/channels/selective_fading_model.h
new file mode 100644
index 0000000000..c68328d2d7
--- /dev/null
+++ b/gr-channels/include/gnuradio/channels/selective_fading_model.h
@@ -0,0 +1,82 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2013 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_CHANNELS_SELECTIVE_FADING_MODEL_H
+#define INCLUDED_CHANNELS_SELECTIVE_FADING_MODEL_H
+
+#include <gnuradio/channels/api.h>
+#include <gnuradio/sync_block.h>
+#include <gnuradio/types.h>
+
+namespace gr {
+  namespace channels {
+    
+    const float default_delays[] =  {0.0,0.1,0.5};
+    const float default_mags[] =    {1.0,0.8,0.3};
+
+    /*!
+     * \brief fading simulator
+     * \ingroup channel_models_blk
+     *
+     * \details
+     * This block implements a basic fading model simulator that can
+     * be used to help evaluate, design, and test various signals,
+     * waveforms, and algorithms. 
+     */
+    class CHANNELS_API selective_fading_model : virtual public sync_block
+    {
+    public:
+      // gr::channels::channel_model::sptr
+      typedef boost::shared_ptr<selective_fading_model> sptr;
+
+      /*! \brief Build the channel simulator.
+       *
+       * \param N The number of sinusiods to use in simulating the channel 8 is a good value 
+       * \param fDTs    normalized maximum doppler frequency, fD * Ts
+       * \param LOS     include Line-of-Site path? selects between Rayleigh (NLOS) and Rician (LOS) models
+       * \param K       Rician factor (ratio of the specular power to the scattered power)
+       * \param seed    a random number to seed the noise generators
+       */
+      static sptr make(unsigned int N,
+                float fDTs,
+                bool LOS,
+                float K,
+                int seed,
+                std::vector<float> delays,
+                std::vector<float> mags,
+                int ntaps
+                );
+      
+      virtual float fDTs() = 0;
+      virtual float K() = 0;
+      virtual float step() = 0;
+
+      virtual void set_fDTs(float fDTs) = 0;
+      virtual void set_K(float K) = 0;
+      virtual void set_step(float step) = 0;
+
+    };
+
+  } /* namespace channels */
+} /* namespace gr */
+
+#endif /* INCLUDED_CHANNELS_SELECTIVE_FADING_MODEL_H */
diff --git a/gr-channels/lib/CMakeLists.txt b/gr-channels/lib/CMakeLists.txt
index bd0151143d..46c90671c2 100644
--- a/gr-channels/lib/CMakeLists.txt
+++ b/gr-channels/lib/CMakeLists.txt
@@ -44,6 +44,8 @@ endif(ENABLE_GR_CTRLPORT)
 list(APPEND channels_sources
   channel_model_impl.cc
   fading_model_impl.cc
+  selective_fading_model_impl.cc
+  flat_fader_impl.cc
 )
 
 #Add Windows DLL resource file if using MSVC
diff --git a/gr-channels/lib/fading_model_impl.cc b/gr-channels/lib/fading_model_impl.cc
index a39a6cf44f..4ea4d1274e 100644
--- a/gr-channels/lib/fading_model_impl.cc
+++ b/gr-channels/lib/fading_model_impl.cc
@@ -50,37 +50,8 @@ namespace gr {
       : sync_block("fading_model",
 		       io_signature::make(1, 1, sizeof(gr_complex)),
 		       io_signature::make(1, 1, sizeof(gr_complex))),
-        seed_1((int)seed),
-        dist_1(-M_PI, M_PI),
-        rv_1( seed_1, dist_1 ), // U(-pi,pi)
-        
-        seed_2((int)seed+1),
-        dist_2(0, 1),
-        rv_2( seed_2, dist_2 ), // U(0,1)
-        
-        d_N(N),
-        d_fDTs(fDTs),
-        d_theta(rv_1()),
-        d_theta_los(rv_1()),
-        d_step( powf(0.00125*fDTs, 1.1) ),  // max step size approximated from Table 2
-        d_m(0),
-        d_K(K),
-        d_LOS(LOS),
-        
-        d_psi(d_N+1, 0),
-        d_phi(d_N+1, 0),
-        
-        d_table(8*1024),
-        
-        scale_sin(sqrtf(2.0/d_N)),
-        scale_los(sqrtf(d_K)/sqrtf(d_K+1)),
-        scale_nlos(1/sqrtf(d_K+1))
+        d_fader(N,fDTs, LOS, K, seed)
     {
-        // generate initial phase values
-        for(int i=0; i<d_N+1; i++){
-            d_psi[i] = rv_1();
-            d_phi[i] = rv_1();
-        }
     }
 
     fading_model_impl::~fading_model_impl()
@@ -138,17 +109,6 @@ namespace gr {
 #endif /* GR_CTRLPORT */
     }
 
-    void 
-    fading_model_impl::update_theta()
-    {
-        d_theta += (d_step*rv_2());
-        if(d_theta > M_PI){
-            d_theta = M_PI; d_step = -d_step;
-        } else if(d_theta < -M_PI){
-            d_theta = -M_PI; d_step = -d_step;
-        }
-    }
-
     int 
     fading_model_impl::work (int noutput_items,
         gr_vector_const_void_star &input_items,
@@ -156,48 +116,9 @@ namespace gr {
     {
         const gr_complex* in = (const gr_complex*) input_items[0];
         gr_complex* out = (gr_complex*) output_items[0];
-
         for(int i=0; i<noutput_items; i++){
-            gr_complex H(0,0);
-
-            for(int n=1; n<d_N; n++){
-                float alpha_n = (2*M_PI*n - M_PI + d_theta)/4*d_N;
-#if FASTSINCOS == 1
-                float s_i = scale_sin*gr::fxpt::cos(gr::fxpt::float_to_fixed(2*M_PI*d_fDTs*d_m*gr::fxpt::cos(gr::fxpt::float_to_fixed(alpha_n))+d_psi[n+1]));
-                float s_q = scale_sin*gr::fxpt::cos(gr::fxpt::float_to_fixed(2*M_PI*d_fDTs*d_m*gr::fxpt::sin(gr::fxpt::float_to_fixed(alpha_n))+d_phi[n+1]));
-#elif FASTSINCOS == 2
-                float s_i = scale_sin*d_table.cos(2*M_PI*d_fDTs*d_m*d_table.cos(alpha_n)+d_psi[n+1]);
-                float s_q = scale_sin*d_table.cos(2*M_PI*d_fDTs*d_m*d_table.sin(alpha_n)+d_phi[n+1]);
-
-#else
-                float s_i = scale_sin*cos(2*M_PI*d_fDTs*d_m*cos(alpha_n)+d_psi[n+1]);
-                float s_q = scale_sin*cos(2*M_PI*d_fDTs*d_m*sin(alpha_n)+d_phi[n+1]);
-#endif
-
-                H += gr_complex(s_i, s_q);
-            }
-
-            if(d_LOS){
-#if FASTSINCOS == 1
-                float los_i = gr::fxpt::cos(gr::fxpt::float_to_fixed(2*M_PI*d_fDTs*d_m*gr::fxpt::cos(gr::fxpt::float_to_fixed(d_theta_los)) + d_psi[0]));
-                float los_q = gr::fxpt::sin(gr::fxpt::float_to_fixed(2*M_PI*d_fDTs*d_m*gr::fxpt::cos(gr::fxpt::float_to_fixed(d_theta_los)) + d_psi[0]));
-#elif FASTSINCOS == 2
-                float los_i = d_table.cos(2*M_PI*d_fDTs*d_m*d_table.cos(d_theta_los) + d_psi[0]);
-                float los_q = d_table.sin(2*M_PI*d_fDTs*d_m*d_table.cos(d_theta_los) + d_psi[0]);
-#else
-                float los_i = cos(2*M_PI*d_fDTs*d_m*cos(d_theta_los) + d_psi[0]);
-                float los_q = sin(2*M_PI*d_fDTs*d_m*cos(d_theta_los) + d_psi[0]);
-#endif
-
-                H = H*scale_nlos + gr_complex(los_i,los_q)*scale_los;
-                }
-
-            out[i] = in[i]*H;
-            d_m++;
-            update_theta();
-
+            out[i] = in[i] * d_fader.next_sample();
         }
-
         return noutput_items;
     }
 
diff --git a/gr-channels/lib/fading_model_impl.h b/gr-channels/lib/fading_model_impl.h
index 3b816b6679..cba992958d 100644
--- a/gr-channels/lib/fading_model_impl.h
+++ b/gr-channels/lib/fading_model_impl.h
@@ -25,6 +25,7 @@
 
 #include <gnuradio/sync_block.h>
 #include <gnuradio/channels/fading_model.h>
+#include "flat_fader_impl.h"
 
 //#include <iostream>
 #include <boost/format.hpp>
@@ -39,36 +40,7 @@ namespace gr {
     class CHANNELS_API fading_model_impl : public fading_model
     {
     private:
-        // initial theta variate generator
-        boost::mt19937 seed_1;
-        boost::uniform_real<> dist_1; // U(-pi,pi)
-        boost::variate_generator<boost::mt19937&, boost::uniform_real<> > rv_1;
-
-        // random walk variate
-        boost::mt19937 seed_2;
-        boost::uniform_real<> dist_2; // U(-pi,pi)
-        boost::variate_generator<boost::mt19937&, boost::uniform_real<> > rv_2;
-
-        int d_N; // number of sinusoids
-        float d_fDTs;  // normalized maximum doppler frequency
-        double d_theta; // random walk variable (RWP)
-        float d_theta_los;
-        float d_step;  // maximum random walk step size
-        uint64_t d_m;  // sample counter
-
-        float d_K;     // Rician factor (ratio of the specular power to the scattered power)
-        bool d_LOS;    // LOS path exists? chooses Rician (LOS) vs Rayleigh (NLOS) model.
-
-        std::vector<float> d_psi; // in-phase initial phase
-        std::vector<float> d_phi; // quadrature initial phase
-
-        std::vector<float>  d_costable;
-
-        sincostable d_table;
-
-        float scale_sin, scale_los, scale_nlos; 
-
-        void update_theta();
+      gr::channels::flat_fader_impl d_fader;
 
     public:
       fading_model_impl(unsigned int N, float fDTs, bool LOS, float K, int seed);
@@ -78,13 +50,13 @@ namespace gr {
             gr_vector_const_void_star &input_items,
             gr_vector_void_star &output_items);
 
-      virtual float fDTs(){ return d_fDTs; }
-      virtual float K(){ return d_K; }
-      virtual float step(){ return d_step; }
+      virtual float fDTs(){ return d_fader.d_fDTs; }
+      virtual float K(){ return d_fader.d_K; }
+      virtual float step(){ return d_fader.d_step; }
 
-      virtual void set_fDTs(float fDTs){ d_fDTs = fDTs;  d_step = powf(0.00125*fDTs, 1.1); }
-      virtual void set_K(float K){ d_K = K; scale_los = sqrtf(d_K)/sqrtf(d_K+1); scale_nlos = (1/sqrtf(d_K+1)); }
-      virtual void set_step(float step){ d_step = step; }
+      virtual void set_fDTs(float fDTs){ d_fader.d_fDTs = fDTs;  d_fader.d_step = powf(0.00125*fDTs, 1.1); }
+      virtual void set_K(float K){ d_fader.d_K = K; d_fader.scale_los = sqrtf(d_fader.d_K)/sqrtf(d_fader.d_K+1); d_fader.scale_nlos = (1/sqrtf(d_fader.d_K+1)); }
+      virtual void set_step(float step){ d_fader.d_step = step; }
 
     };
 
diff --git a/gr-channels/lib/flat_fader_impl.cc b/gr-channels/lib/flat_fader_impl.cc
new file mode 100644
index 0000000000..af35e29ef4
--- /dev/null
+++ b/gr-channels/lib/flat_fader_impl.cc
@@ -0,0 +1,117 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2013 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 <flat_fader_impl.h>
+
+namespace gr {
+  namespace channels {
+
+    flat_fader_impl::flat_fader_impl(unsigned int N, float fDTs, bool LOS, float K, int seed ) :
+        seed_1((int)seed),
+        dist_1(-M_PI, M_PI),
+        rv_1( seed_1, dist_1 ), // U(-pi,pi)
+        
+        seed_2((int)seed+1),
+        dist_2(0, 1),
+        rv_2( seed_2, dist_2 ), // U(0,1)
+        
+        d_N(N),
+        d_fDTs(fDTs),
+        d_theta(rv_1()),
+        d_theta_los(rv_1()),
+        d_step( powf(0.00125*fDTs, 1.1) ),  // max step size approximated from Table 2
+        d_m(0),
+        d_K(K),
+        d_LOS(LOS),
+        
+        d_psi(d_N+1, 0),
+        d_phi(d_N+1, 0),
+        
+        d_table(8*1024),
+        
+        scale_sin(sqrtf(2.0/d_N)),
+        scale_los(sqrtf(d_K)/sqrtf(d_K+1)),
+        scale_nlos(1/sqrtf(d_K+1))
+    {
+        // generate initial phase values
+        for(int i=0; i<d_N+1; i++){
+          d_psi[i] = rv_1();
+          d_phi[i] = rv_1();
+        }
+    }
+    
+    
+    gr_complex flat_fader_impl::next_sample(){
+        gr_complex H(0,0);
+
+        for(int n=1; n<d_N; n++){
+            float alpha_n = (2*M_PI*n - M_PI + d_theta)/4*d_N;
+#if FASTSINCOS == 1
+            float s_i = scale_sin*gr::fxpt::cos(gr::fxpt::float_to_fixed(2*M_PI*d_fDTs*d_m*gr::fxpt::cos(gr::fxpt::float_to_fixed(alpha_n))+d_psi[n+1]));
+            float s_q = scale_sin*gr::fxpt::cos(gr::fxpt::float_to_fixed(2*M_PI*d_fDTs*d_m*gr::fxpt::sin(gr::fxpt::float_to_fixed(alpha_n))+d_phi[n+1]));
+#elif FASTSINCOS == 2
+            float s_i = scale_sin*d_table.cos(2*M_PI*d_fDTs*d_m*d_table.cos(alpha_n)+d_psi[n+1]);
+            float s_q = scale_sin*d_table.cos(2*M_PI*d_fDTs*d_m*d_table.sin(alpha_n)+d_phi[n+1]);
+
+#else
+            float s_i = scale_sin*cos(2*M_PI*d_fDTs*d_m*cos(alpha_n)+d_psi[n+1]);
+            float s_q = scale_sin*cos(2*M_PI*d_fDTs*d_m*sin(alpha_n)+d_phi[n+1]);
+#endif
+
+            H += gr_complex(s_i, s_q);
+        }
+
+        if(d_LOS){
+#if FASTSINCOS == 1
+            float los_i = gr::fxpt::cos(gr::fxpt::float_to_fixed(2*M_PI*d_fDTs*d_m*gr::fxpt::cos(gr::fxpt::float_to_fixed(d_theta_los)) + d_psi[0]));
+            float los_q = gr::fxpt::sin(gr::fxpt::float_to_fixed(2*M_PI*d_fDTs*d_m*gr::fxpt::cos(gr::fxpt::float_to_fixed(d_theta_los)) + d_psi[0]));
+#elif FASTSINCOS == 2
+            float los_i = d_table.cos(2*M_PI*d_fDTs*d_m*d_table.cos(d_theta_los) + d_psi[0]);
+            float los_q = d_table.sin(2*M_PI*d_fDTs*d_m*d_table.cos(d_theta_los) + d_psi[0]);
+#else
+            float los_i = cos(2*M_PI*d_fDTs*d_m*cos(d_theta_los) + d_psi[0]);
+            float los_q = sin(2*M_PI*d_fDTs*d_m*cos(d_theta_los) + d_psi[0]);
+#endif
+
+            H = H*scale_nlos + gr_complex(los_i,los_q)*scale_los;
+            }
+
+        //out[i] = in[i]*H;
+        d_m++;
+        update_theta();
+        return H;
+
+    }
+
+    void flat_fader_impl::update_theta()
+    {
+        d_theta += (d_step*rv_2());
+        if(d_theta > M_PI){
+            d_theta = M_PI; d_step = -d_step;
+        } else if(d_theta < -M_PI){
+            d_theta = -M_PI; d_step = -d_step;
+        }
+    }
+
+  } /* namespace channels */
+} /* namespace gr */
+
diff --git a/gr-channels/lib/flat_fader_impl.h b/gr-channels/lib/flat_fader_impl.h
new file mode 100644
index 0000000000..766ac43d89
--- /dev/null
+++ b/gr-channels/lib/flat_fader_impl.h
@@ -0,0 +1,82 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2013 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 FLAT_FADER_IMPL_H
+#define FLAT_FADER_IMPL_H
+
+#include <gnuradio/io_signature.h>
+#include <iostream>
+
+#include <boost/format.hpp>
+#include <boost/random.hpp>
+
+#include <gnuradio/fxpt.h>
+#include <sincostable.h>
+
+// FASTSINCOS:  0 = slow native,  1 = gr::fxpt impl,  2 = sincostable.h
+#define FASTSINCOS  2
+
+namespace gr {
+  namespace channels { 
+
+    class flat_fader_impl {
+      private:
+        // initial theta variate generator
+        boost::mt19937 seed_1;
+        boost::uniform_real<> dist_1; // U(-pi,pi)
+        boost::variate_generator<boost::mt19937&, boost::uniform_real<> > rv_1;
+    
+        // random walk variate
+        boost::mt19937 seed_2;
+        boost::uniform_real<> dist_2; // U(-pi,pi)
+        boost::variate_generator<boost::mt19937&, boost::uniform_real<> > rv_2;
+      
+      public:
+        int d_N; // number of sinusoids
+        float d_fDTs;  // normalized maximum doppler frequency
+        double d_theta; // random walk variable (RWP)
+        float d_theta_los;
+        float d_step;  // maximum random walk step size
+        uint64_t d_m;  // sample counter
+        
+        float d_K;     // Rician factor (ratio of the specular power to the scattered power)
+        bool d_LOS;    // LOS path exists? chooses Rician (LOS) vs Rayleigh (NLOS) model.
+        
+        std::vector<float> d_psi; // in-phase initial phase
+        std::vector<float> d_phi; // quadrature initial phase
+        
+        std::vector<float>  d_costable;
+        
+        sincostable d_table;
+        
+        float scale_sin, scale_los, scale_nlos;
+    
+        void update_theta();
+    
+        flat_fader_impl(unsigned int N, float fDTs, bool LOS, float K, int seed);
+        gr_complex next_sample();
+    
+    }; /* class flat_fader_impl */
+  } /* namespace channels */
+} /* namespace gr */
+
+#endif // FLAT_FADER_IMPL_H
diff --git a/gr-channels/lib/selective_fading_model_impl.cc b/gr-channels/lib/selective_fading_model_impl.cc
new file mode 100644
index 0000000000..7beebf2e65
--- /dev/null
+++ b/gr-channels/lib/selective_fading_model_impl.cc
@@ -0,0 +1,169 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2013 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 "selective_fading_model_impl.h"
+#include <gnuradio/io_signature.h>
+#include <iostream>
+
+#include <boost/format.hpp>
+#include <boost/random.hpp>
+
+#include <gnuradio/fxpt.h>
+#include <sincostable.h>
+
+
+// FASTSINCOS:  0 = slow native,  1 = gr::fxpt impl,  2 = sincostable.h
+#define FASTSINCOS  2
+
+
+namespace gr {
+  namespace channels {
+    
+    selective_fading_model::sptr
+    selective_fading_model::make( unsigned int N, float fDTs, bool LOS, float K, int seed, std::vector<float> delays, std::vector<float> mags, int ntaps)
+    {
+      return gnuradio::get_initial_sptr
+	(new selective_fading_model_impl( N, fDTs, LOS, K, seed, delays, mags, ntaps));
+    }
+
+    // Block constructor
+    selective_fading_model_impl::selective_fading_model_impl( unsigned int N, float fDTs, bool LOS, float K, int seed, std::vector<float> delays, std::vector<float> mags, int ntaps )
+      : sync_block("selective_fading_model",
+		       io_signature::make(1, 1, sizeof(gr_complex)),
+		       io_signature::make(1, 1, sizeof(gr_complex))),
+        d_delays(delays),
+        d_mags(mags),
+        d_sintable(1024)
+    {
+        if(mags.size() != delays.size())
+            throw std::runtime_error("magnitude and delay vectors must be the same length!");
+
+        for(size_t i=0; i<mags.size(); i++){
+            d_faders.push_back(new gr::channels::flat_fader_impl(N,fDTs, LOS, K, seed+i));
+        }
+    
+        // set up tap history
+//        int ntaps = 10;
+        set_history(1+ntaps);
+        d_taps.resize(ntaps, gr_complex(0,0));
+    }
+
+    selective_fading_model_impl::~selective_fading_model_impl()
+    {
+        for(size_t i=0; i<d_faders.size(); i++){
+            delete d_faders[i];
+        }
+    }
+
+    int 
+    selective_fading_model_impl::work (int noutput_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];
+
+        // loop over each output sample
+        for(int i=0; i<noutput_items; i++){
+
+            // clear the current values in each tap
+            for(size_t j=0; j<d_taps.size(); j++){
+                d_taps[j] = gr_complex(0,0);
+            }
+            
+            // add each flat fading component to the taps
+            for(size_t j=0; j<d_faders.size(); j++){
+                gr_complex ff_H(d_faders[j]->next_sample());
+                for(size_t k=0; k<d_taps.size(); k++){
+                    float dist = k-d_delays[j];
+                    float interpmag = d_sintable.sinc(2*M_PI*dist);       
+                    d_taps[k] += ff_H * interpmag * d_mags[j];
+                }
+            }
+
+            // apply the taps and generate output
+            gr_complex sum(0,0);
+            for(size_t j=0; j<d_taps.size(); j++){
+                sum += in[i+j] * d_taps[d_taps.size()-j-1];
+            }
+
+            // assign output 
+            out[i] = sum;
+        }
+
+        // return all outputs
+        return noutput_items;
+    }
+
+    void
+    selective_fading_model_impl::setup_rpc()
+    {
+#ifdef GR_CTRLPORT
+    add_rpc_variable(
+        rpcbasic_sptr(new rpcbasic_register_get<selective_fading_model, float >(
+            alias(), "fDTs",
+            &selective_fading_model::fDTs,
+            pmt::mp(0), pmt::mp(1), pmt::mp(0.01),
+            "Hz*Sec", "normalized maximum doppler frequency (fD*Ts)",
+            RPC_PRIVLVL_MIN, DISPTIME | DISPOPTSTRIP)));
+    add_rpc_variable(
+        rpcbasic_sptr(new rpcbasic_register_set<selective_fading_model, float >(
+            alias(), "fDTs",
+            &selective_fading_model::set_fDTs,
+            pmt::mp(0), pmt::mp(1), pmt::mp(0.01),
+            "Hz*Sec", "normalized maximum doppler frequency (fD*Ts)",
+            RPC_PRIVLVL_MIN, DISPTIME | DISPOPTSTRIP)));
+
+    add_rpc_variable(
+        rpcbasic_sptr(new rpcbasic_register_get<selective_fading_model, float >(
+            alias(), "K",
+            &selective_fading_model::K,
+            pmt::mp(0), pmt::mp(8), pmt::mp(4),
+            "Ratio", "Rician factor (ratio of the specular power to the scattered power)",
+            RPC_PRIVLVL_MIN, DISPTIME | DISPOPTSTRIP)));
+    add_rpc_variable(
+        rpcbasic_sptr(new rpcbasic_register_set<selective_fading_model, float >(
+            alias(), "K",
+            &selective_fading_model::set_K,
+            pmt::mp(0), pmt::mp(8), pmt::mp(4),
+            "Ratio", "Rician factor (ratio of the specular power to the scattered power)",
+            RPC_PRIVLVL_MIN, DISPTIME | DISPOPTSTRIP)));
+
+    add_rpc_variable(
+        rpcbasic_sptr(new rpcbasic_register_get<selective_fading_model, float >(
+            alias(), "step",
+            &selective_fading_model::step,
+            pmt::mp(0), pmt::mp(8), pmt::mp(4),
+            "radians", "Maximum step size for random walk angle per sample",
+            RPC_PRIVLVL_MIN, DISPTIME | DISPOPTSTRIP)));
+    add_rpc_variable(
+        rpcbasic_sptr(new rpcbasic_register_set<selective_fading_model, float >(
+            alias(), "step",
+            &selective_fading_model::set_step,
+            pmt::mp(0), pmt::mp(1), pmt::mp(0.00001),
+            "radians", "Maximum step size for random walk angle per sample",
+            RPC_PRIVLVL_MIN, DISPTIME | DISPOPTSTRIP)));
+#endif /* GR_CTRLPORT */
+    }
+
+  } /* namespace channels */
+} /* namespace gr */
diff --git a/gr-channels/lib/selective_fading_model_impl.h b/gr-channels/lib/selective_fading_model_impl.h
new file mode 100644
index 0000000000..769077aea2
--- /dev/null
+++ b/gr-channels/lib/selective_fading_model_impl.h
@@ -0,0 +1,79 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2013 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_CHANNELS_SELECTIVE_FADING_MODEL_IMPL_H
+#define INCLUDED_CHANNELS_SELECTIVE_FADING_MODEL_IMPL_H
+
+#include <gnuradio/sync_block.h>
+#include <gnuradio/channels/selective_fading_model.h>
+#include "flat_fader_impl.h"
+
+//#include <iostream>
+#include <boost/format.hpp>
+#include <boost/random.hpp>
+
+#include <gnuradio/fxpt.h>
+#include <sincostable.h>
+
+namespace gr {
+  namespace channels {
+
+    class CHANNELS_API selective_fading_model_impl : public selective_fading_model
+    {
+    private:
+      std::vector<gr::channels::flat_fader_impl*> d_faders;
+      std::vector<float> d_delays;
+      std::vector<float> d_mags;
+      sincostable d_sintable;
+
+    public:
+      selective_fading_model_impl(unsigned int N, float fDTs, bool LOS, float K, int seed, std::vector<float> delays, std::vector<float> mags, int ntaps);
+      ~selective_fading_model_impl();
+      void setup_rpc();
+      int work (int noutput_items,
+            gr_vector_const_void_star &input_items,
+            gr_vector_void_star &output_items);
+      std::vector<gr_complex> d_taps;
+
+      virtual float fDTs(){ return d_faders[0]->d_fDTs; }
+      virtual float K(){ return d_faders[0]->d_K; }
+      virtual float step(){ return d_faders[0]->d_step; }
+
+      virtual void set_fDTs(float fDTs){ 
+            BOOST_FOREACH( gr::channels::flat_fader_impl* fader, d_faders )
+            { fader->d_fDTs = fDTs;  fader->d_step = powf(0.00125*fDTs, 1.1); }
+            }
+      virtual void set_K(float K){ 
+            BOOST_FOREACH( gr::channels::flat_fader_impl* fader, d_faders )
+            { fader->d_K = K; fader->scale_los = sqrtf(fader->d_K)/sqrtf(fader->d_K+1); fader->scale_nlos = (1/sqrtf(fader->d_K+1)); }
+            }
+      virtual void set_step(float step){ 
+            BOOST_FOREACH( gr::channels::flat_fader_impl* fader, d_faders )
+            { fader->d_step = step; }
+            }
+
+    };
+
+  } /* namespace channels */
+} /* namespace gr */
+
+#endif /* INCLUDED_CHANNELS_SELECTIVE_FADING_MODEL_IMPL_H */
diff --git a/gr-channels/lib/sincostable.h b/gr-channels/lib/sincostable.h
index be5e6a482c..2a5adb6f4c 100644
--- a/gr-channels/lib/sincostable.h
+++ b/gr-channels/lib/sincostable.h
@@ -26,6 +26,9 @@ class sincostable {
         int idx = (((int)(x*d_scale)) + d_sz) % d_sz;
         return d_cos[idx];
         }
+    const float sinc(float x){
+        return x==0?1:sin(x)/x;
+        }
 };
 
 #endif
diff --git a/gr-channels/swig/channels_swig.i b/gr-channels/swig/channels_swig.i
index f27dc08e56..fb7ada7dae 100644
--- a/gr-channels/swig/channels_swig.i
+++ b/gr-channels/swig/channels_swig.i
@@ -30,10 +30,13 @@
 %{
 #include "gnuradio/channels/channel_model.h"
 #include "gnuradio/channels/fading_model.h"
+#include "gnuradio/channels/selective_fading_model.h"
 %}
 
 %include "gnuradio/channels/channel_model.h"
 %include "gnuradio/channels/fading_model.h"
+%include "gnuradio/channels/selective_fading_model.h"
 
 GR_SWIG_BLOCK_MAGIC2(channels, channel_model);
 GR_SWIG_BLOCK_MAGIC2(channels, fading_model);
+GR_SWIG_BLOCK_MAGIC2(channels, selective_fading_model);
author	Tim O'Shea <tim.oshea753@gmail.com>	2013-06-06 16:15:52 -0400
committer	Tim O'Shea <tim.oshea753@gmail.com>	2013-06-06 16:15:52 -0400
commit	9896a6727bc1446e0597ad51cc4305acfb46ff1b (patch)
tree	ab6fcc2f599d65ef1c46e2f2e1a78cf67068985f
parent	553c06df3dcc913219e6462131861a937acb8b5e (diff)