diff --git a/cmds/statsd/src/atoms.proto b/cmds/statsd/src/atoms.proto
index 53d9673..8572517 100644
--- a/cmds/statsd/src/atoms.proto
+++ b/cmds/statsd/src/atoms.proto
@@ -27,6 +27,7 @@
 import "frameworks/base/core/proto/android/bluetooth/enums.proto";
 import "frameworks/base/core/proto/android/os/enums.proto";
 import "frameworks/base/core/proto/android/server/enums.proto";
+import "frameworks/base/core/proto/android/server/location/enums.proto";
 import "frameworks/base/core/proto/android/service/procstats_enum.proto";
 import "frameworks/base/core/proto/android/stats/enums.proto";
 import "frameworks/base/core/proto/android/stats/launcher/launcher.proto";
@@ -118,7 +119,7 @@
         ResourceConfigurationChanged resource_configuration_changed = 66;
         BluetoothEnabledStateChanged bluetooth_enabled_state_changed = 67;
         BluetoothConnectionStateChanged bluetooth_connection_state_changed = 68;
-        // 69 is blank but need not be.
+        GpsSignalQualityChanged gps_signal_quality_changed = 69;
         UsbConnectorStateChanged usb_connector_state_changed = 70;
         SpeakerImpedanceReported speaker_impedance_reported = 71;
         HardwareFailed hardware_failed = 72;
@@ -486,7 +487,6 @@
     optional State state = 3;
 }
 
-
 /**
  * Logs when GPS state changes.
  *
@@ -503,6 +503,16 @@
     optional State state = 2;
 }
 
+/**
+ * Logs when GPS signal quality.
+ *
+ * Logged from:
+ *   /frameworks/base/location/java/com/android/internal/location/gnssmetrics/GnssMetrics.java
+ */
+message GpsSignalQualityChanged {
+    optional android.server.location.GpsSignalQualityEnum level = 1;
+}
+
 
 /**
  * Logs when a sync manager sync state changes.
diff --git a/core/proto/android/server/location/enums.proto b/core/proto/android/server/location/enums.proto
new file mode 100644
index 0000000..b6dc589
--- /dev/null
+++ b/core/proto/android/server/location/enums.proto
@@ -0,0 +1,30 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+syntax = "proto2";
+
+package android.server.location;
+
+option java_outer_classname = "ServerLocationProtoEnums";
+option java_multiple_files = true;
+
+// GPS Signal Quality levels,
+// primarily used by location/java/com/android/internal/location/gnssmetrics/GnssMetrics.java
+enum GpsSignalQualityEnum {
+    GPS_SIGNAL_QUALITY_UNKNOWN = -1;
+    GPS_SIGNAL_QUALITY_POOR = 0;
+    GPS_SIGNAL_QUALITY_GOOD = 1;
+}
diff --git a/location/java/com/android/internal/location/gnssmetrics/GnssMetrics.java b/location/java/com/android/internal/location/gnssmetrics/GnssMetrics.java
index 8a02a82..057a4ae 100644
--- a/location/java/com/android/internal/location/gnssmetrics/GnssMetrics.java
+++ b/location/java/com/android/internal/location/gnssmetrics/GnssMetrics.java
@@ -20,9 +20,12 @@
 import android.os.connectivity.GpsBatteryStats;
 import android.os.SystemProperties;
 
+import android.server.location.ServerLocationProtoEnums;
+
 import android.text.format.DateUtils;
 import android.util.Base64;
 import android.util.Log;
+import android.util.StatsLog;
 import android.util.TimeUtils;
 
 import java.util.Arrays;
@@ -39,11 +42,17 @@
 
   private static final String TAG = GnssMetrics.class.getSimpleName();
 
+  /* Constant which indicates GPS signal quality is as yet unknown */
+  public static final int GPS_SIGNAL_QUALITY_UNKNOWN =
+          ServerLocationProtoEnums.GPS_SIGNAL_QUALITY_UNKNOWN; // -1
+
   /* Constant which indicates GPS signal quality is poor */
-  public static final int GPS_SIGNAL_QUALITY_POOR = 0;
+  public static final int GPS_SIGNAL_QUALITY_POOR =
+      ServerLocationProtoEnums.GPS_SIGNAL_QUALITY_POOR; // 0
 
   /* Constant which indicates GPS signal quality is good */
-  public static final int GPS_SIGNAL_QUALITY_GOOD = 1;
+  public static final int GPS_SIGNAL_QUALITY_GOOD =
+      ServerLocationProtoEnums.GPS_SIGNAL_QUALITY_GOOD; // 1
 
   /* Number of GPS signal quality levels */
   public static final int NUM_GPS_SIGNAL_QUALITY_LEVELS = GPS_SIGNAL_QUALITY_GOOD + 1;
@@ -329,11 +338,15 @@
     /* Last reported Top Four Average CN0 */
     private double mLastAverageCn0;
 
+    /* Last reported signal quality bin (based on Top Four Average CN0) */
+    private int mLastSignalLevel;
+
     public GnssPowerMetrics(IBatteryStats stats) {
       mBatteryStats = stats;
       // Used to initialize the variable to a very small value (unachievable in practice) so that
       // the first CNO report will trigger an update to BatteryStats
       mLastAverageCn0 = -100.0;
+      mLastSignalLevel = GPS_SIGNAL_QUALITY_UNKNOWN;
     }
 
     /**
@@ -384,8 +397,13 @@
       if (Math.abs(avgCn0 - mLastAverageCn0) < REPORTING_THRESHOLD_DB_HZ) {
         return;
       }
+      int signalLevel = getSignalLevel(avgCn0);
+      if (signalLevel != mLastSignalLevel) {
+        StatsLog.write(StatsLog.GPS_SIGNAL_QUALITY_CHANGED, signalLevel);
+        mLastSignalLevel = signalLevel;
+      }
       try {
-        mBatteryStats.noteGpsSignalQuality(getSignalLevel(avgCn0));
+        mBatteryStats.noteGpsSignalQuality(signalLevel);
         mLastAverageCn0 = avgCn0;
       } catch (Exception e) {
         Log.w(TAG, "Exception", e);