Added AWGN channel to SRSUE and SRSENB

lib/include/srslte/phy/channel/channel.h

@@ -39,6 +39,10 @@ public:
     // General
     bool enable = false;
 
+    // AWGN options
+    bool  awgn_enable  = false;
+    float awgn_n0_dBfs = -30.0f;
+
     // Fading options
     bool        fading_enable = false;
     std::string fading_model  = "none";
@@ -71,6 +75,7 @@ public:
 private:
   srslte_channel_fading_t* fading[SRSLTE_MAX_CHANNELS] = {};
   srslte_channel_delay_t*  delay[SRSLTE_MAX_CHANNELS]  = {};
+  srslte_channel_awgn_t*   awgn                        = nullptr;
   srslte_channel_hst_t*    hst                      = nullptr; // HST has no buffers / no multiple instance is required
   srslte_channel_rlf_t*    rlf                      = nullptr; // RLF has no buffers / no multiple instance is required
   cf_t*                    buffer_in                = nullptr;

lib/src/phy/channel/channel.cc

@@ -74,6 +74,13 @@ channel::channel(const channel::args_t& channel_args, uint32_t _nof_channels)
     }
   }
 
+  // Create AWGN channnel
+  if (channel_args.awgn_enable && ret == SRSLTE_SUCCESS) {
+    awgn = (srslte_channel_awgn_t*)calloc(sizeof(srslte_channel_awgn_t), 1);
+    ret  = srslte_channel_awgn_init(awgn, 1234);
+    srslte_channel_awgn_set_n0(awgn, args.awgn_n0_dBfs);
+  }
+
   // Create high speed train
   if (channel_args.hst_enable && ret == SRSLTE_SUCCESS) {
     hst = (srslte_channel_hst_t*)calloc(sizeof(srslte_channel_hst_t), 1);
@@ -101,6 +108,11 @@ channel::~channel()
     free(buffer_out);
   }
 
+  if (awgn) {
+    srslte_channel_awgn_free(awgn);
+    free(awgn);
+  }
+
   if (hst) {
     srslte_channel_hst_free(hst);
     free(hst);
@@ -143,6 +155,11 @@ void channel::run(cf_t*                     in[SRSLTE_MAX_CHANNELS],
           // Copy input buffer
           memcpy(buffer_in, in[i], sizeof(cf_t) * len);
 
+          if (awgn) {
+            srslte_channel_awgn_run_c(awgn, buffer_in, buffer_out, len);
+            memcpy(buffer_in, buffer_out, sizeof(cf_t) * len);
+          }
+
           if (fading[i]) {
             srslte_channel_fading_execute(fading[i], buffer_in, buffer_out, len, t.full_secs + t.frac_secs);
             memcpy(buffer_in, buffer_out, sizeof(cf_t) * len);

srsenb/enb.conf.example

@@ -175,6 +175,10 @@ pusch_max_mcs    = 16
 # Channel emulator options:
 # enable:            Enable/Disable internal Downlink/Uplink channel emulator
 #
+# -- AWGN Generator
+# awgn.enable:       Enable/disable AWGN generator
+# awgn.n0:           Noise power in dBfs
+#
 # -- Fading emulator
 # fading.enable:     Enable/disable fading simulator
 # fading.model:      Fading model + maximum doppler (E.g. none, epa5, eva70, etu300, etc)
@@ -201,6 +205,10 @@ pusch_max_mcs    = 16
 [channel.dl]
 #enable        = false
 
+[channel.dl.awgn]
+#enable        = false
+#n0            = -30
+
 [channel.dl.fading]
 #enable        = false
 #model         = none
@@ -226,6 +234,10 @@ pusch_max_mcs    = 16
 [channel.ul]
 #enable        = false
 
+[channel.ul.awgn]
+#enable        = false
+#n0            = -30
+
 [channel.ul.fading]
 #enable        = false
 #model         = none

srsenb/src/main.cc

@@ -134,6 +134,8 @@ void parse_args(all_args_t* args, int argc, char* argv[])
 
     /* Downlink Channel emulator section */
     ("channel.dl.enable", bpo::value<bool>(&args->phy.dl_channel_args.enable)->default_value(false), "Enable/Disable internal Downlink channel emulator")
+    ("channel.dl.awgn.enable", bpo::value<bool>(&args->phy.dl_channel_args.awgn_enable)->default_value(false), "Enable/Disable AWGN simulator")
+    ("channel.dl.awgn.n0", bpo::value<float>(&args->phy.dl_channel_args.awgn_n0_dBfs)->default_value(-30.0f), "Noise level in decibels full scale (dBfs)")
     ("channel.dl.fading.enable", bpo::value<bool>(&args->phy.dl_channel_args.fading_enable)->default_value(false), "Enable/Disable Fading model")
     ("channel.dl.fading.model", bpo::value<std::string>(&args->phy.dl_channel_args.fading_model)->default_value("none"), "Fading model + maximum doppler (E.g. none, epa5, eva70, etu300, etc)")
     ("channel.dl.delay.enable", bpo::value<bool>(&args->phy.dl_channel_args.delay_enable)->default_value(false), "Enable/Disable Delay simulator")
@@ -151,6 +153,8 @@ void parse_args(all_args_t* args, int argc, char* argv[])
 
     /* Uplink Channel emulator section */
     ("channel.ul.enable", bpo::value<bool>(&args->phy.ul_channel_args.enable)->default_value(false), "Enable/Disable internal Uplink channel emulator")
+    ("channel.ul.awgn.enable", bpo::value<bool>(&args->phy.ul_channel_args.awgn_enable)->default_value(false), "Enable/Disable AWGN simulator")
+    ("channel.ul.awgn.n0", bpo::value<float>(&args->phy.ul_channel_args.awgn_n0_dBfs)->default_value(-30.0f), "Noise level in decibels full scale (dBfs)")
     ("channel.ul.fading.enable", bpo::value<bool>(&args->phy.ul_channel_args.fading_enable)->default_value(false), "Enable/Disable Fading model")
     ("channel.ul.fading.model", bpo::value<std::string>(&args->phy.ul_channel_args.fading_model)->default_value("none"), "Fading model + maximum doppler (E.g. none, epa5, eva70, etu300, etc)")
     ("channel.ul.delay.enable", bpo::value<bool>(&args->phy.ul_channel_args.delay_enable)->default_value(false), "Enable/Disable Delay simulator")

srsenb/src/phy/phy_common.cc

@@ -72,7 +72,7 @@ bool phy_common::init(const phy_cell_cfg_list_t&   cell_list_,
   pthread_cond_init(&mtch_cvar, nullptr);
 
   // Instantiate DL channel emulator
-  if (params.ul_channel_args.enable) {
+  if (params.dl_channel_args.enable) {
     dl_channel = srslte::channel_ptr(new srslte::channel(params.dl_channel_args, 1));
     dl_channel->set_srate((uint32_t)srslte_sampling_freq_hz(cell_list[0].cell.nof_prb));
   }

srsue/src/main.cc

@@ -172,6 +172,8 @@ static int parse_args(all_args_t* args, int argc, char* argv[])
 
     /* Downlink Channel emulator section */
     ("channel.dl.enable", bpo::value<bool>(&args->phy.dl_channel_args.enable)->default_value(false), "Enable/Disable internal Downlink channel emulator")
+    ("channel.dl.awgn.enable", bpo::value<bool>(&args->phy.dl_channel_args.awgn_enable)->default_value(false), "Enable/Disable AWGN simulator")
+    ("channel.dl.awgn.n0", bpo::value<float>(&args->phy.dl_channel_args.awgn_n0_dBfs)->default_value(-30.0f), "Noise level in decibels full scale (dBfs)")
     ("channel.dl.fading.enable", bpo::value<bool>(&args->phy.dl_channel_args.fading_enable)->default_value(false), "Enable/Disable Fading model")
     ("channel.dl.fading.model", bpo::value<std::string>(&args->phy.dl_channel_args.fading_model)->default_value("none"), "Fading model + maximum doppler (E.g. none, epa5, eva70, etu300, etc)")
     ("channel.dl.delay.enable", bpo::value<bool>(&args->phy.dl_channel_args.delay_enable)->default_value(false), "Enable/Disable Delay simulator")
@@ -189,6 +191,8 @@ static int parse_args(all_args_t* args, int argc, char* argv[])
 
     /* Uplink Channel emulator section */
     ("channel.ul.enable", bpo::value<bool>(&args->phy.ul_channel_args.enable)->default_value(false), "Enable/Disable internal Uplink channel emulator")
+    ("channel.ul.awgn.enable", bpo::value<bool>(&args->phy.ul_channel_args.awgn_enable)->default_value(false), "Enable/Disable AWGN simulator")
+    ("channel.ul.awgn.n0", bpo::value<float>(&args->phy.ul_channel_args.awgn_n0_dBfs)->default_value(-30.0f), "Noise level in decibels full scale (dBfs)")
     ("channel.ul.fading.enable", bpo::value<bool>(&args->phy.ul_channel_args.fading_enable)->default_value(false), "Enable/Disable Fading model")
     ("channel.ul.fading.model", bpo::value<std::string>(&args->phy.ul_channel_args.fading_model)->default_value("none"), "Fading model + maximum doppler (E.g. none, epa5, eva70, etu300, etc)")
     ("channel.ul.delay.enable", bpo::value<bool>(&args->phy.ul_channel_args.delay_enable)->default_value(false), "Enable/Disable Delay simulator")

srsue/ue.conf.example

@@ -186,6 +186,10 @@ enable = false
 # Channel emulator options:
 # enable:            Enable/Disable internal Downlink/Uplink channel emulator
 #
+# -- AWGN Generator
+# awgn.enable:       Enable/disable AWGN generator
+# awgn.n0:           Noise power in dBfs
+#
 # -- Fading emulator
 # fading.enable:     Enable/disable fading simulator
 # fading.model:      Fading model + maximum doppler (E.g. none, epa5, eva70, etu300, etc)
@@ -212,6 +216,10 @@ enable = false
 [channel.dl]
 #enable        = false
 
+[channel.dl.awgn]
+#enable        = false
+#n0            = -30
+
 [channel.dl.fading]
 #enable        = false
 #model         = none
@@ -237,6 +245,10 @@ enable = false
 [channel.ul]
 #enable        = false
 
+[channel.ul.awgn]
+#enable        = false
+#n0            = -30
+
 [channel.ul.fading]
 #enable        = false
 #model         = none