diff options
| -rw-r--r-- | location/java/android/location/GnssMeasurement.java | 55 |
1 files changed, 53 insertions, 2 deletions
diff --git a/location/java/android/location/GnssMeasurement.java b/location/java/android/location/GnssMeasurement.java index cd2af1b85f50..bd46ffdf7e57 100644 --- a/location/java/android/location/GnssMeasurement.java +++ b/location/java/android/location/GnssMeasurement.java @@ -901,8 +901,59 @@ public final class GnssMeasurement implements Parcelable { /** * Gets 'Accumulated Delta Range' state. * - * <p>It indicates whether {@link #getAccumulatedDeltaRangeMeters()} is reset or there is a - * cycle slip (indicating 'loss of lock'). + * <p>This indicates the state of the {@link #getAccumulatedDeltaRangeMeters()} measurement. See + * the table below for a detailed interpretation of each state. + * + * <table border="1"> + * <thead> + * <tr> + * <th>ADR_STATE</th> + * <th>Time of relevance</th> + * <th>Interpretation</th> + * </tr> + * </thead> + * <tbody> + * <tr> + * <td>UNKNOWN</td> + * <td>ADR(t)</td> + * <td>No valid carrier phase information is available at time t.</td> + * </tr> + * <tr> + * <td>VALID</td> + * <td>ADR(t)</td> + * <td>Valid carrier phase information is available at time t. This indicates that this + * measurement can be used as a reference for future measurements. However, to compare it to + * previous measurements to compute delta range, other bits should be checked. Specifically, + * it can be used for delta range computation if it is valid and has no reset or cycle slip at + * this epoch i.e. if VALID_BIT == 1 && CYCLE_SLIP_BIT == 0 && RESET_BIT == 0.</td> + * </tr> + * <tr> + * <td>RESET</td> + * <td>ADR(t) - ADR(t-1)</td> + * <td>Carrier phase accumulation has been restarted between current time t and previous time + * t-1. This indicates that this measurement can be used as a reference for future measurements, + * but it should not be compared to previous measurements to compute delta range.</td> + * </tr> + * <tr> + * <td>CYCLE_SLIP</td> + * <td>ADR(t) - ADR(t-1)</td> + * <td>Cycle slip(s) have been detected between the current time t and previous time t-1. This + * indicates that this measurement can be used as a reference for future measurements. Clients + * can use a measurement with a cycle slip to compute delta range against previous measurements + * at their own risk.</td> + * </tr> + * <tr> + * <td>HALF_CYCLE_RESOLVED</td> + * <td>ADR(t)</td> + * <td>Half cycle ambiguity is resolved at time t.</td> + * </tr> + * <tr> + * <td>HALF_CYCLE_REPORTED</td> + * <td>ADR(t)</td> + * <td>Half cycle ambiguity is reported at time t.</td> + * </tr> + * </tbody> + * </table> */ @AdrState public int getAccumulatedDeltaRangeState() { |