Changeset 2390

Timestamp:

12/19/06 21:06:37 (6 years ago)

Author:

jgaeddert

Message:

adding lock detector

Location:

components/CostasLoopBPSK/trunk/CostasLoopBPSK

Files:

• CostasLoopBPSK.cpp (modified) (10 diffs)
• CostasLoopBPSK.h (modified) (1 diff)
• plot_results.m (modified) (2 diffs)

components/CostasLoopBPSK/trunk/CostasLoopBPSK/CostasLoopBPSK.cpp

@@ -35 +35 @@
 
 #undef VERBOSE
-#define LOGGING
+#undef LOGGING
+#define LOCK_DETECTOR
 #define PI 3.1415926536
+
+#ifdef LOGGING
+#define LOG_SIZE_MAX 10000
+#endif
 
 CostasLoopBPSK_i::CostasLoopBPSK_i(const char *uuid, omni_condition *condition) : Resource_impl(uuid), component_running(condition) 
@@ -42 +47 @@
     dataIn = new standardInterfaces_i::complexShort_p("IF_in");
     dataOut = new standardInterfaces_i::complexShort_u("baseband_out");
+
+    // initialize algorithm variables
+    e_i = 10.0f;
+    e_q = 100.0f;
+    zeta_lock = 0.0025f;
+    lock = false;
+    lock_detect_threshold = 1.5f;
 
     //Create the thread for the writer's processing function 
@@ -174 +186 @@
 
     float alpha, beta, xi, k1, Ac, BT;
-    Ac = 100.0f;
+    Ac = 15000.0f;
 
     // define loop filter
@@ -184 +196 @@
     alpha = 2*xi*beta;
 
-    float tmp2(0.0f), q_hat(0.0f), q_prime(0.0f), wcTs(1.57f);
+    float tmp2(0.0f), q_hat(0.0f), q_prime(0.0f), wcTs(0.0f), cv(0.0f);
 
 #ifdef LOGGING
@@ -201 +213 @@
     std::ofstream output_log;
     output_log.open("output_log.dat");
+
+#ifdef LOCK_DETECTOR
+    std::ofstream lock_detect_log;
+    lock_detect_log.open("lock_detect_log.dat");
+#endif
+
+    int log_size_counter(0);
 #endif
 
@@ -213 +232 @@
         input_data_length = I_in->length();
 
+        mem->lock_counter = 0;
+
         for (i=0; i<input_data_length; i++)
         {
             
-#ifdef VERBOSE
-            std::cout << "  " << (*I_in)[i] << "      " << (*Q_in)[i] << std::endl;
-#endif
-
             //phase detection
             // TODO: perform complex mixer without using floats
@@ -235 +252 @@
 #endif
 
+#ifdef LOCK_DETECTOR
+            mem->e_i = (1-mem->zeta_lock)*(mem->e_i) + 
+                          (mem->zeta_lock)*float( abs( I_out[i] ) );
+            mem->e_q = (1-mem->zeta_lock)*(mem->e_q) + 
+                          (mem->zeta_lock)*float( abs( Q_out[i] ) );
+            mem->lock_detect = mem->e_i / mem->e_q;
+//            std::cout << ":: e_i = " << mem->e_i << std::endl;
+//            std::cout << ":: e_q = " << mem->e_q << std::endl;
+//            std::cout << ":: lock_detect = " << mem->lock_detect << std::endl;
+            if ( mem->lock_detect > mem->lock_detect_threshold )
+            {
+                mem->lock = true;
+                mem->lock_counter++;
+            }
+//            std::cout << ":: lock_counter = " << mem->lock_counter << std::endl;
+#endif
+
             q_prime = pd2*beta + tmp2;
             q_hat = alpha*pd2 + q_prime;
             tmp2 = q_prime;
-            nco_control = nco_control + wcTs + q_hat;
+            cv = wcTs + q_hat;
+
+            if (cv > PI/2 )
+                cv = PI/2;
+            else if ( cv < -PI/2 )
+                cv = -PI/2;
+            else;
+
+            nco_control = nco_control + cv;
 
             if ( nco_control > 2*PI )
@@ -251 +293 @@
 
 #ifdef LOGGING
-            input_log       << (*I_in)[i] << "  " << (*Q_in)[i] << std::endl;
-            pd2_log         << pd2 << std::endl;
-            nco_control_log << nco_control << std::endl;
-            nco_log         << nco_i << "  " << nco_q << std::endl;
-            output_log      << I_out[i] << "  " << Q_out[i] << std::endl;
+            if (log_size_counter < LOG_SIZE_MAX )
+            {
+                input_log       << (*I_in)[i] << "  " << (*Q_in)[i] << std::endl;
+                pd2_log         << pd2 << std::endl;
+                nco_control_log << nco_control << std::endl;
+                nco_log         << nco_i << "  " << nco_q << std::endl;
+                output_log      << I_out[i] << "  " << Q_out[i] << std::endl;
+#ifdef LOCK_DETECTOR
+                lock_detect_log << mem->e_i << "  " << mem->e_q << std::endl;
+#endif
+            }
+            log_size_counter++;
 #endif
         }
@@ -261 +310 @@
         mem->dataIn->bufferEmptied();
         mem->dataOut->pushPacket(I_out, Q_out);
+
+#ifdef VERBOSE
+#ifdef LOCK_DETECTOR
+        std::cout << "CostasLoopBPSK: locked on " << mem->lock_counter << " / "
+                  << input_data_length << " samples" << std::endl;
+#endif
+#endif
+
     }
 #ifdef LOGGING
@@ -268 +325 @@
     nco_log.close();
     output_log.close();
-#endif
-
-}
-
-    
+#ifdef LOCK_DETECTOR
+    lock_detect_log.close();
+#endif
+#endif
+
+}
+
+    

components/CostasLoopBPSK/trunk/CostasLoopBPSK/CostasLoopBPSK.h

@@ -89 +89 @@
 
         // --- algorithm variables ---
+
+        // lock detection varaiables
+        float e_i;
+        float e_q;
+        bool lock;
+        int lock_counter;
+        float lock_detect;
+        float lock_detect_threshold;
+        float zeta_lock;
         
 };

components/CostasLoopBPSK/trunk/CostasLoopBPSK/plot_results.m

@@ -7 +7 @@
 load nco_control_log.dat;
 load nco_log.dat;
-load pd_log.dat;
 load pd2_log.dat;
 load baseband.txt;
@@ -37 +36 @@
 );
 
-figure;
-plot(...
-     t(1:N),pd_log(1:N,2),"-;pd-Q;",...
-     t(1:N),output_log(1:N,2),"-;Q-out;"
-);
 
 figure;