Merge "Add valid satellite PVT fields in SatellitePvt" into sc-dev
diff --git a/gnss/aidl/android/hardware/gnss/GnssMeasurement.aidl b/gnss/aidl/android/hardware/gnss/GnssMeasurement.aidl
index 336e927..58f29c5 100644
--- a/gnss/aidl/android/hardware/gnss/GnssMeasurement.aidl
+++ b/gnss/aidl/android/hardware/gnss/GnssMeasurement.aidl
@@ -625,6 +625,17 @@
* The position and velocity must be in ECEF coordinates.
*
* If the data is available, gnssMeasurementFlags must contain HAS_SATELLITE_PVT.
+ *
+ * If SatellitePvt is derived from Broadcast ephemeris, then the position is already w.r.t.
+ * the antenna phase center. However, if SatellitePvt is derived from other modeled orbits,
+ * such as long-term-orbits, or precise orbits, then the orbits may have been computed w.r.t.
+ * the satellite center of mass, and then GNSS vendors are expected to correct for the effect
+ * on different phase centers (can differ by meters) of different GNSS signals (e.g. L1, L5)
+ * on the reported satellite position. Accordingly, we might observe a different satellite
+ * position reported for L1 GnssMeasurement struct compared to L5 GnssMeasurement struct.
+ *
+ * If receivedSvTimeNs is not fully decoded, Satellite PVT could still be reported and
+ * receivedSvTimeNs uncertainty field would be used to provide confidence.
*/
SatellitePvt satellitePvt;
diff --git a/gnss/aidl/android/hardware/gnss/SatelliteClockInfo.aidl b/gnss/aidl/android/hardware/gnss/SatelliteClockInfo.aidl
index 844fd1c..4b7d5d6 100644
--- a/gnss/aidl/android/hardware/gnss/SatelliteClockInfo.aidl
+++ b/gnss/aidl/android/hardware/gnss/SatelliteClockInfo.aidl
@@ -24,6 +24,14 @@
/**
* Satellite hardware code bias of the reported code type w.r.t
* ionosphere-free measurement in meters.
+ *
+ * When broadcast ephemeris is used, this is the offset caused
+ * by the satellite hardware delays at different frequencies;
+ * e.g. in IS-GPS-705D, this term is described in Section
+ * 20.3.3.3.1.2.1.
+ *
+ * For GPS this term is ~10ns, and affects the satellite position
+ * computation by less than a millimeter.
*/
double satHardwareCodeBiasMeters;
@@ -31,9 +39,20 @@
* Satellite time correction for ionospheric-free signal measurement
* (meters). The satellite clock correction for the given signal type
* = satTimeCorrectionMeters - satHardwareCodeBiasMeters.
+ *
+ * When broadcast ephemeris is used, this is the offset modeled in the
+ * clock terms broadcast over the air by the satellites;
+ * e.g. in IS-GPS-200H, Section 20.3.3.3.3.1, this term is
+ * ∆tsv = af0 + af1(t - toc) + af2(t - toc)^2 + ∆tr.
+ *
+ * If another source of ephemeris is used for SatellitePvt, then the
+ * equivalent value of satTimeCorrection must be provided.
+ *
+ * For GPS this term is ~1ms, and affects the satellite position
+ * computation by ~1m.
*/
double satTimeCorrectionMeters;
/** Satellite clock drift (meters per second). */
double satClkDriftMps;
-}
\ No newline at end of file
+}