Add basebandCn0Dbhz to GnssMeasurement

The new basebandCn0DbHz is the carrier-to-noise density measured at the
baseband. The old Cn0DbHz is measured at the attenna port. Adding
the new field so that ecosystem will report both and avoid reporting
inconsistent signal strengths in one field. See go/r-gnss-hal for
detailed design.

Bug: 136136192
Test: atest GnssMeasurementTest
Change-Id: Ia8d3711e7422db5cae05d66138a3fae61bec0ae1

1 files changed, 64 insertions, 7 deletions

diff --git a/location/java/android/location/GnssMeasurement.java b/location/java/android/location/GnssMeasurement.java
index 9013a9603559..70abbb3019fc 100644
--- a/location/java/android/location/GnssMeasurement.java
+++ b/location/java/android/location/GnssMeasurement.java
@@ -16,9 +16,11 @@
 
 package android.location;
 
+import android.annotation.FloatRange;
 import android.annotation.IntDef;
 import android.annotation.NonNull;
 import android.annotation.TestApi;
+import android.hardware.gnss.V1_0.IGnssMeasurementCallback.GnssMeasurementFlags;
 import android.os.Parcel;
 import android.os.Parcelable;
 
@@ -37,6 +39,7 @@ public final class GnssMeasurement implements Parcelable {
     private long mReceivedSvTimeNanos;
     private long mReceivedSvTimeUncertaintyNanos;
     private double mCn0DbHz;
+    private double mBasebandCn0DbHz;
     private double mPseudorangeRateMetersPerSecond;
     private double mPseudorangeRateUncertaintyMetersPerSecond;
     private int mAccumulatedDeltaRangeState;
@@ -51,16 +54,20 @@ public final class GnssMeasurement implements Parcelable {
     private double mAutomaticGainControlLevelInDb;
     @NonNull private String mCodeType;
 
-    // The following enumerations must be in sync with the values declared in gps.h
+    // The following enumerations must be in sync with the values declared in GNSS HAL.
 
     private static final int HAS_NO_FLAGS = 0;
-    private static final int HAS_SNR = (1<<0);
-    private static final int HAS_CARRIER_FREQUENCY = (1<<9);
-    private static final int HAS_CARRIER_CYCLES = (1<<10);
-    private static final int HAS_CARRIER_PHASE = (1<<11);
-    private static final int HAS_CARRIER_PHASE_UNCERTAINTY = (1<<12);
-    private static final int HAS_AUTOMATIC_GAIN_CONTROL = (1<<13);
+    private static final int HAS_SNR = GnssMeasurementFlags.HAS_SNR;
+    private static final int HAS_CARRIER_FREQUENCY = GnssMeasurementFlags.HAS_CARRIER_FREQUENCY;
+    private static final int HAS_CARRIER_CYCLES = GnssMeasurementFlags.HAS_CARRIER_CYCLES;
+    private static final int HAS_CARRIER_PHASE = GnssMeasurementFlags.HAS_CARRIER_PHASE;
+    private static final int HAS_CARRIER_PHASE_UNCERTAINTY =
+            GnssMeasurementFlags.HAS_CARRIER_PHASE_UNCERTAINTY;
+    private static final int HAS_AUTOMATIC_GAIN_CONTROL =
+            GnssMeasurementFlags.HAS_AUTOMATIC_GAIN_CONTROL;
+
     private static final int HAS_CODE_TYPE = (1 << 14);
+    private static final int HAS_BASEBAND_CN0 = (1 << 15);
 
     /**
      * The status of the multipath indicator.
@@ -240,6 +247,7 @@ public final class GnssMeasurement implements Parcelable {
         mReceivedSvTimeNanos = measurement.mReceivedSvTimeNanos;
         mReceivedSvTimeUncertaintyNanos = measurement.mReceivedSvTimeUncertaintyNanos;
         mCn0DbHz = measurement.mCn0DbHz;
+        mBasebandCn0DbHz = measurement.mBasebandCn0DbHz;
         mPseudorangeRateMetersPerSecond = measurement.mPseudorangeRateMetersPerSecond;
         mPseudorangeRateUncertaintyMetersPerSecond =
                 measurement.mPseudorangeRateUncertaintyMetersPerSecond;
@@ -788,6 +796,49 @@ public final class GnssMeasurement implements Parcelable {
     }
 
     /**
+     * Returns {@code true} if {@link #getBasebandCn0DbHz()} is available, {@code false} otherwise.
+     */
+    public boolean hasBasebandCn0DbHz() {
+        return isFlagSet(HAS_BASEBAND_CN0);
+    }
+
+    /**
+     * Gets the baseband carrier-to-noise density in dB-Hz.
+     *
+     * <p>Typical range: 0-50 dB-Hz.
+     *
+     * <p>The value contains the measured C/N0 for the signal at the baseband. This is typically
+     * a few dB weaker than the value estimated for C/N0 at the antenna port, which is reported
+     * in {@link #getCn0DbHz()}.
+     */
+    @FloatRange(from = 0, to = 50)
+    public double getBasebandCn0DbHz() {
+        return mBasebandCn0DbHz;
+    }
+
+    /**
+     * Sets the baseband carrier-to-noise density in dB-Hz.
+     *
+     * @hide
+     */
+    @TestApi
+    public void setBasebandCn0DbHz(double value) {
+        setFlag(HAS_BASEBAND_CN0);
+        mBasebandCn0DbHz = value;
+    }
+
+    /**
+     * Resets the baseband carrier-to-noise density in dB-Hz.
+     *
+     * @hide
+     */
+    @TestApi
+    public void resetBasebandCn0DbHz() {
+        resetFlag(HAS_BASEBAND_CN0);
+        mBasebandCn0DbHz = Double.NaN;
+    }
+
+    /**
      * Gets the Pseudorange rate at the timestamp in m/s.
      *
      * <p>The error estimate for this value is
@@ -1400,6 +1451,7 @@ public final class GnssMeasurement implements Parcelable {
             gnssMeasurement.mSnrInDb = parcel.readDouble();
             gnssMeasurement.mAutomaticGainControlLevelInDb = parcel.readDouble();
             gnssMeasurement.mCodeType = parcel.readString();
+            gnssMeasurement.mBasebandCn0DbHz = parcel.readDouble();
 
             return gnssMeasurement;
         }
@@ -1433,6 +1485,7 @@ public final class GnssMeasurement implements Parcelable {
         parcel.writeDouble(mSnrInDb);
         parcel.writeDouble(mAutomaticGainControlLevelInDb);
         parcel.writeString(mCodeType);
+        parcel.writeDouble(mBasebandCn0DbHz);
     }
 
     @Override
@@ -1461,6 +1514,9 @@ public final class GnssMeasurement implements Parcelable {
 
         builder.append(String.format(format, "Cn0DbHz", mCn0DbHz));
 
+        builder.append(String.format(format, "BasebandCn0DbHz",
+                hasBasebandCn0DbHz() ? mBasebandCn0DbHz : null));
+
         builder.append(String.format(
                 formatWithUncertainty,
                 "PseudorangeRateMetersPerSecond",
@@ -1536,6 +1592,7 @@ public final class GnssMeasurement implements Parcelable {
         resetSnrInDb();
         resetAutomaticGainControlLevel();
         resetCodeType();
+        resetBasebandCn0DbHz();
     }
 
     private void setFlag(int flag) {