diff --git a/src/algorithms/tracking/adapters/gps_l1_ca_dll_pll_c_aid_tracking.cc b/src/algorithms/tracking/adapters/gps_l1_ca_dll_pll_c_aid_tracking.cc
index 436c68e60..fe9eb4d4c 100644
--- a/src/algorithms/tracking/adapters/gps_l1_ca_dll_pll_c_aid_tracking.cc
+++ b/src/algorithms/tracking/adapters/gps_l1_ca_dll_pll_c_aid_tracking.cc
@@ -60,7 +60,9 @@ GpsL1CaDllPllCAidTracking::GpsL1CaDllPllCAidTracking(
     std::string dump_filename;
     std::string default_item_type = "gr_complex";
     float pll_bw_hz;
+    float pll_bw_narrow_hz;
     float dll_bw_hz;
+    float dll_bw_narrow_hz;
     float early_late_space_chips;
     item_type_ = configuration->property(role + ".item_type", default_item_type);
     //vector_length = configuration->property(role + ".vector_length", 2048);
@@ -69,6 +71,8 @@ GpsL1CaDllPllCAidTracking::GpsL1CaDllPllCAidTracking(
     dump = configuration->property(role + ".dump", false);
     pll_bw_hz = configuration->property(role + ".pll_bw_hz", 50.0);
     dll_bw_hz = configuration->property(role + ".dll_bw_hz", 2.0);
+    pll_bw_narrow_hz = configuration->property(role + ".pll_bw_narrow_hz", 20.0);
+    dll_bw_narrow_hz = configuration->property(role + ".dll_bw_narrow_hz", 2.0);
     early_late_space_chips = configuration->property(role + ".early_late_space_chips", 0.5);
     std::string default_dump_filename = "./track_ch";
     dump_filename = configuration->property(role + ".dump_filename",
@@ -88,6 +92,8 @@ GpsL1CaDllPllCAidTracking::GpsL1CaDllPllCAidTracking(
                     dump_filename,
                     pll_bw_hz,
                     dll_bw_hz,
+                    pll_bw_narrow_hz,
+                    dll_bw_narrow_hz,
                     early_late_space_chips);
             DLOG(INFO) << "tracking(" << tracking_cc->unique_id() << ")";
     }else if(item_type_.compare("cshort") == 0)
@@ -102,6 +108,8 @@ GpsL1CaDllPllCAidTracking::GpsL1CaDllPllCAidTracking(
                 dump_filename,
                 pll_bw_hz,
                 dll_bw_hz,
+                pll_bw_narrow_hz,
+                dll_bw_narrow_hz,
                 early_late_space_chips);
         DLOG(INFO) << "tracking(" << tracking_sc->unique_id() << ")";
     }else
diff --git a/src/algorithms/tracking/gnuradio_blocks/gps_l1_ca_dll_pll_c_aid_tracking_cc.cc b/src/algorithms/tracking/gnuradio_blocks/gps_l1_ca_dll_pll_c_aid_tracking_cc.cc
index b7304512a..eba5c0795 100644
--- a/src/algorithms/tracking/gnuradio_blocks/gps_l1_ca_dll_pll_c_aid_tracking_cc.cc
+++ b/src/algorithms/tracking/gnuradio_blocks/gps_l1_ca_dll_pll_c_aid_tracking_cc.cc
@@ -67,10 +67,12 @@ gps_l1_ca_dll_pll_c_aid_make_tracking_cc(
         std::string dump_filename,
         float pll_bw_hz,
         float dll_bw_hz,
+        float pll_bw_narrow_hz,
+        float dll_bw_narrow_hz,
         float early_late_space_chips)
 {
     return gps_l1_ca_dll_pll_c_aid_tracking_cc_sptr(new gps_l1_ca_dll_pll_c_aid_tracking_cc(if_freq,
-            fs_in, vector_length, queue, dump, dump_filename, pll_bw_hz, dll_bw_hz, early_late_space_chips));
+            fs_in, vector_length, queue, dump, dump_filename, pll_bw_hz, dll_bw_hz,pll_bw_narrow_hz, dll_bw_narrow_hz, early_late_space_chips));
 }
 
 
@@ -106,6 +108,8 @@ gps_l1_ca_dll_pll_c_aid_tracking_cc::gps_l1_ca_dll_pll_c_aid_tracking_cc(
         std::string dump_filename,
         float pll_bw_hz,
         float dll_bw_hz,
+        float pll_bw_narrow_hz,
+        float dll_bw_narrow_hz,
         float early_late_space_chips) :
         gr::block("gps_l1_ca_dll_pll_c_aid_tracking_cc", gr::io_signature::make(1, 1, sizeof(gr_complex)),
                 gr::io_signature::make(1, 1, sizeof(Gnss_Synchro)))
@@ -129,6 +133,8 @@ gps_l1_ca_dll_pll_c_aid_tracking_cc::gps_l1_ca_dll_pll_c_aid_tracking_cc(
     // Initialize tracking  ==========================================
     d_pll_bw_hz=pll_bw_hz;
     d_dll_bw_hz=dll_bw_hz;
+    d_pll_bw_narrow_hz=pll_bw_narrow_hz;
+    d_dll_bw_narrow_hz=dll_bw_narrow_hz;
     d_code_loop_filter.set_DLL_BW(d_dll_bw_hz);
     d_carrier_loop_filter.set_params(10.0, d_pll_bw_hz,2);
 
@@ -394,8 +400,8 @@ int gps_l1_ca_dll_pll_c_aid_tracking_cc::general_work (int noutput_items, gr_vec
 					current_synchro_data.symbol_integration_enabled=true;
 					// UPDATE INTEGRATION TIME
 	            	CURRENT_INTEGRATION_TIME_S = static_cast<double>(GPS_CA_TELEMETRY_SYMBOLS_PER_BIT)*GPS_L1_CA_CODE_PERIOD;
-				    d_code_loop_filter.set_DLL_BW(d_dll_bw_hz);
-				    d_carrier_loop_filter.set_params(10.0, d_pll_bw_hz/5,2);
+				    d_code_loop_filter.set_DLL_BW(d_dll_bw_narrow_hz);
+				    d_carrier_loop_filter.set_params(10.0, d_pll_bw_narrow_hz,2);
 					enable_dll_pll=true;
 
 				}else{
diff --git a/src/algorithms/tracking/gnuradio_blocks/gps_l1_ca_dll_pll_c_aid_tracking_cc.h b/src/algorithms/tracking/gnuradio_blocks/gps_l1_ca_dll_pll_c_aid_tracking_cc.h
index 3d4cf3272..5df1ad8c4 100644
--- a/src/algorithms/tracking/gnuradio_blocks/gps_l1_ca_dll_pll_c_aid_tracking_cc.h
+++ b/src/algorithms/tracking/gnuradio_blocks/gps_l1_ca_dll_pll_c_aid_tracking_cc.h
@@ -64,6 +64,8 @@ gps_l1_ca_dll_pll_c_aid_make_tracking_cc(long if_freq,
                                    std::string dump_filename,
                                    float pll_bw_hz,
                                    float dll_bw_hz,
+                                   float pll_bw_narrow_hz,
+                                   float dll_bw_narrow_hz,
                                    float early_late_space_chips);
 
 
@@ -96,6 +98,8 @@ private:
             std::string dump_filename,
             float pll_bw_hz,
             float dll_bw_hz,
+            float pll_bw_narrow_hz,
+            float dll_bw_narrow_hz,
             float early_late_space_chips);
 
     gps_l1_ca_dll_pll_c_aid_tracking_cc(long if_freq,
@@ -106,6 +110,8 @@ private:
             std::string dump_filename,
             float pll_bw_hz,
             float dll_bw_hz,
+            float pll_bw_narrow_hz,
+            float dll_bw_narrow_hz,
             float early_late_space_chips);
 
     // tracking configuration vars
@@ -145,6 +151,8 @@ private:
     // tracking vars
     float d_dll_bw_hz;
     float d_pll_bw_hz;
+    float d_dll_bw_narrow_hz;
+    float d_pll_bw_narrow_hz;
     double d_code_freq_chips;
     double d_code_phase_step_chips;
     double d_carrier_doppler_hz;
diff --git a/src/algorithms/tracking/gnuradio_blocks/gps_l1_ca_dll_pll_c_aid_tracking_sc.cc b/src/algorithms/tracking/gnuradio_blocks/gps_l1_ca_dll_pll_c_aid_tracking_sc.cc
index d74738e4d..12b8351bf 100644
--- a/src/algorithms/tracking/gnuradio_blocks/gps_l1_ca_dll_pll_c_aid_tracking_sc.cc
+++ b/src/algorithms/tracking/gnuradio_blocks/gps_l1_ca_dll_pll_c_aid_tracking_sc.cc
@@ -66,10 +66,12 @@ gps_l1_ca_dll_pll_c_aid_make_tracking_sc(
         std::string dump_filename,
         float pll_bw_hz,
         float dll_bw_hz,
+        float pll_bw_narrow_hz,
+        float dll_bw_narrow_hz,
         float early_late_space_chips)
 {
     return gps_l1_ca_dll_pll_c_aid_tracking_sc_sptr(new gps_l1_ca_dll_pll_c_aid_tracking_sc(if_freq,
-            fs_in, vector_length, queue, dump, dump_filename, pll_bw_hz, dll_bw_hz, early_late_space_chips));
+            fs_in, vector_length, queue, dump, dump_filename, pll_bw_hz, dll_bw_hz, pll_bw_narrow_hz, dll_bw_narrow_hz, early_late_space_chips));
 }
 
 
@@ -94,6 +96,8 @@ gps_l1_ca_dll_pll_c_aid_tracking_sc::gps_l1_ca_dll_pll_c_aid_tracking_sc(
         std::string dump_filename,
         float pll_bw_hz,
         float dll_bw_hz,
+        float pll_bw_narrow_hz,
+        float dll_bw_narrow_hz,
         float early_late_space_chips) :
         gr::block("gps_l1_ca_dll_pll_c_aid_tracking_sc", gr::io_signature::make(1, 1, sizeof(lv_16sc_t)),
                 gr::io_signature::make(1, 1, sizeof(Gnss_Synchro)))
@@ -108,6 +112,10 @@ gps_l1_ca_dll_pll_c_aid_tracking_sc::gps_l1_ca_dll_pll_c_aid_tracking_sc(
     d_correlation_length_samples = static_cast<int>(d_vector_length);
 
     // Initialize tracking  ==========================================
+    d_pll_bw_hz=pll_bw_hz;
+    d_dll_bw_hz=dll_bw_hz;
+    d_pll_bw_narrow_hz=pll_bw_narrow_hz;
+    d_dll_bw_narrow_hz=dll_bw_narrow_hz;
     d_code_loop_filter.set_DLL_BW(dll_bw_hz);
     d_carrier_loop_filter.set_params(10.0, pll_bw_hz,2);
 
diff --git a/src/algorithms/tracking/gnuradio_blocks/gps_l1_ca_dll_pll_c_aid_tracking_sc.h b/src/algorithms/tracking/gnuradio_blocks/gps_l1_ca_dll_pll_c_aid_tracking_sc.h
index adfccfb08..ab0efd957 100644
--- a/src/algorithms/tracking/gnuradio_blocks/gps_l1_ca_dll_pll_c_aid_tracking_sc.h
+++ b/src/algorithms/tracking/gnuradio_blocks/gps_l1_ca_dll_pll_c_aid_tracking_sc.h
@@ -67,6 +67,8 @@ gps_l1_ca_dll_pll_c_aid_make_tracking_sc(long if_freq,
                                    std::string dump_filename,
                                    float pll_bw_hz,
                                    float dll_bw_hz,
+                                   float pll_bw_narrow_hz,
+                                   float dll_bw_narrow_hz,
                                    float early_late_space_chips);
 
 
@@ -99,6 +101,8 @@ private:
             std::string dump_filename,
             float pll_bw_hz,
             float dll_bw_hz,
+            float pll_bw_narrow_hz,
+            float dll_bw_narrow_hz,
             float early_late_space_chips);
 
     gps_l1_ca_dll_pll_c_aid_tracking_sc(long if_freq,
@@ -109,6 +113,8 @@ private:
             std::string dump_filename,
             float pll_bw_hz,
             float dll_bw_hz,
+            float pll_bw_narrow_hz,
+            float dll_bw_narrow_hz,
             float early_late_space_chips);
 
     // tracking configuration vars
@@ -148,6 +154,10 @@ private:
     double d_acq_carrier_doppler_hz;
 
     // tracking vars
+    float d_dll_bw_hz;
+    float d_pll_bw_hz;
+    float d_dll_bw_narrow_hz;
+    float d_pll_bw_narrow_hz;
     double d_code_freq_chips;
     double d_code_phase_step_chips;
     double d_carrier_doppler_hz;