Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit ee8daa4b authored by Yu-Han Yang's avatar Yu-Han Yang Committed by Automerger Merge Worker
Browse files

Merge "Fix ADR half cycle ambiguity doc (frameworks/base)" into sc-dev am: cfd524f1 

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/14949570

Change-Id: I26552bd7677bcb2a831ae2304b4703119867e9f4
parents 007fdf66 cfd524f1

location/java/android/location/GnssMeasurement.java

+19 −3
Original line number Diff line number Diff line
@@ -214,6 +214,25 @@ public final class GnssMeasurement implements Parcelable { 
     *

     * <p> When this bit is unset, the {@link #getAccumulatedDeltaRangeMeters()} corresponds to the

     * carrier phase measurement plus an accumulated integer number of carrier half cycles.

     *

     * <p> For signals that have databits, the carrier phase tracking loops typically use a costas

     * loop discriminator.  This type of tracking loop introduces a half-cycle ambiguity that is

     * resolved by searching through the received data for known patterns of databits (e.g. GPS uses

     * the TLM word) which then determines the polarity of the incoming data and resolves the

     * half-cycle ambiguity.

     *

     * <p>Before the half-cycle ambiguity has been resolved it is possible that the ADR_STATE_VALID

     * flag is set:

     *

     * <ul>

     *   <li> In cases where ADR_STATE_HALF_CYCLE_REPORTED is not set, the

     *   ADR_STATE_HALF_CYCLE_RESOLVED flag will not be available. Here, a half wave length will be

     *   added to the returned accumulated delta range uncertainty to indicate the half cycle

     *   ambiguity.

     *   <li> In cases where ADR_STATE_HALF_CYCLE_REPORTED is set, half cycle ambiguity will be

     *   indicated via both the ADR_STATE_HALF_CYCLE_RESOLVED flag and as well a half wave length

     *   added to the returned accumulated delta range uncertainty.

     * </ul>

     */

    public static final int ADR_STATE_HALF_CYCLE_RESOLVED = (1<<3);
@@ -1039,9 +1058,6 @@ public final class GnssMeasurement implements Parcelable { 
     * with integer ambiguity resolution, to determine highly precise relative location between

     * receivers.

     *

     * <p>This includes ensuring that all half-cycle ambiguities are resolved before this value is

     * reported as {@link #ADR_STATE_VALID}.

     *

     * <p>The alignment of the phase measurement will not be adjusted by the receiver so the

     * in-phase and quadrature phase components will have a quarter cycle offset as they do when

     * transmitted from the satellites. If the measurement is from a combination of the in-phase