From cb162534b66bf2685d7c8b54d471c4d0c841f36a Mon Sep 17 00:00:00 2001
From: Yu-Han Yang <yuhany@google.com>
Date: Fri, 20 Dec 2019 11:48:00 -0800
Subject: [PATCH] Make cN0Db and basebandCn0Db ranges consistent with HAL

Bug: 136136192
Test: existing tests passing
Change-Id: I7ffc40f7f00e3d5e141d10025de6fe7886c61ba7
---
 api/current.txt                                     | 4 ++--
 location/java/android/location/GnssMeasurement.java | 9 ++++++---
 2 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/api/current.txt b/api/current.txt
index 86aa80b159bdc..106caa212e10d 100644
--- a/api/current.txt
+++ b/api/current.txt
@@ -23199,12 +23199,12 @@ package android.location {
     method public int getAccumulatedDeltaRangeState();
     method public double getAccumulatedDeltaRangeUncertaintyMeters();
     method public double getAutomaticGainControlLevelDb();
-    method @FloatRange(from=0, to=50) public double getBasebandCn0DbHz();
+    method @FloatRange(from=0, to=63) public double getBasebandCn0DbHz();
     method @Deprecated public long getCarrierCycles();
     method public float getCarrierFrequencyHz();
     method @Deprecated public double getCarrierPhase();
     method @Deprecated public double getCarrierPhaseUncertainty();
-    method public double getCn0DbHz();
+    method @FloatRange(from=0, to=63) public double getCn0DbHz();
     method @NonNull public String getCodeType();
     method public int getConstellationType();
     method public int getMultipathIndicator();
diff --git a/location/java/android/location/GnssMeasurement.java b/location/java/android/location/GnssMeasurement.java
index 70abbb3019fcb..3eeb3a2051e93 100644
--- a/location/java/android/location/GnssMeasurement.java
+++ b/location/java/android/location/GnssMeasurement.java
@@ -778,10 +778,12 @@ public final class GnssMeasurement implements Parcelable {
     /**
      * Gets the Carrier-to-noise density in dB-Hz.
      *
-     * <p>Typical range: 10-50 db-Hz.
+     * <p>Typical range: 10-50 dB-Hz. The range of possible C/N0 values is 0-63 dB-Hz to handle
+     * some edge cases.
      *
      * <p>The value contains the measured C/N0 for the signal at the antenna input.
      */
+    @FloatRange(from = 0, to = 63)
     public double getCn0DbHz() {
         return mCn0DbHz;
     }
@@ -805,13 +807,14 @@ public final class GnssMeasurement implements Parcelable {
     /**
      * Gets the baseband carrier-to-noise density in dB-Hz.
      *
-     * <p>Typical range: 0-50 dB-Hz.
+     * <p>Typical range: 10-50 dB-Hz. The range of possible baseband C/N0 values is 0-63 dB-Hz to
+     * handle some edge cases.
      *
      * <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)
+    @FloatRange(from = 0, to = 63)
     public double getBasebandCn0DbHz() {
         return mBasebandCn0DbHz;
     }