/* * Copyright (C) 2014 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License */ package android.location; import android.annotation.TestApi; import android.annotation.IntDef; import android.os.Parcel; import android.os.Parcelable; import java.lang.annotation.Retention; import java.lang.annotation.RetentionPolicy; /** * A class representing a GNSS satellite measurement, containing raw and computed information. */ public final class GnssMeasurement implements Parcelable { private int mFlags; private int mSvid; private int mConstellationType; private double mTimeOffsetNanos; private int mState; private long mReceivedSvTimeNanos; private long mReceivedSvTimeUncertaintyNanos; private double mCn0DbHz; private double mPseudorangeRateMetersPerSecond; private double mPseudorangeRateUncertaintyMetersPerSecond; private int mAccumulatedDeltaRangeState; private double mAccumulatedDeltaRangeMeters; private double mAccumulatedDeltaRangeUncertaintyMeters; private float mCarrierFrequencyHz; private long mCarrierCycles; private double mCarrierPhase; private double mCarrierPhaseUncertainty; private int mMultipathIndicator; private double mSnrInDb; // The following enumerations must be in sync with the values declared in gps.h 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); /** * The status of the multipath indicator. * @hide */ @Retention(RetentionPolicy.SOURCE) @IntDef({MULTIPATH_INDICATOR_UNKNOWN, MULTIPATH_INDICATOR_DETECTED, MULTIPATH_INDICATOR_NOT_USED}) public @interface MultipathIndicator {} /** * The indicator is not available or the presence or absence of multipath is unknown. */ public static final int MULTIPATH_INDICATOR_UNKNOWN = 0; /** * The measurement shows signs of multi-path. */ public static final int MULTIPATH_INDICATOR_DETECTED = 1; /** * The measurement shows no signs of multi-path. */ public static final int MULTIPATH_INDICATOR_NOT_DETECTED = 2; /** @removed */ public static final int MULTIPATH_INDICATOR_NOT_USED = 2; /** This GNSS measurement's tracking state is invalid or unknown. */ public static final int STATE_UNKNOWN = 0; /** This GNSS measurement's tracking state has code lock. */ public static final int STATE_CODE_LOCK = (1<<0); /** This GNSS measurement's tracking state has bit sync. */ public static final int STATE_BIT_SYNC = (1<<1); /** This GNSS measurement's tracking state has sub-frame sync. */ public static final int STATE_SUBFRAME_SYNC = (1<<2); /** This GNSS measurement's tracking state has time-of-week decoded. */ public static final int STATE_TOW_DECODED = (1<<3); /** This GNSS measurement's tracking state contains millisecond ambiguity. */ public static final int STATE_MSEC_AMBIGUOUS = (1<<4); /** This GNSS measurement's tracking state has symbol sync. */ public static final int STATE_SYMBOL_SYNC = (1<<5); /** This Glonass measurement's tracking state has string sync. */ public static final int STATE_GLO_STRING_SYNC = (1<<6); /** This Glonass measurement's tracking state has time-of-day decoded. */ public static final int STATE_GLO_TOD_DECODED = (1<<7); /** This Beidou measurement's tracking state has D2 bit sync. */ public static final int STATE_BDS_D2_BIT_SYNC = (1<<8); /** This Beidou measurement's tracking state has D2 sub-frame sync. */ public static final int STATE_BDS_D2_SUBFRAME_SYNC = (1<<9); /** This Galileo measurement's tracking state has E1B/C code lock. */ public static final int STATE_GAL_E1BC_CODE_LOCK = (1<<10); /** This Galileo measurement's tracking state has E1C secondary code lock. */ public static final int STATE_GAL_E1C_2ND_CODE_LOCK = (1<<11); /** This Galileo measurement's tracking state has E1B page sync. */ public static final int STATE_GAL_E1B_PAGE_SYNC = (1<<12); /** This SBAS measurement's tracking state has whole second level sync. */ public static final int STATE_SBAS_SYNC = (1<<13); /** * All the GNSS receiver state flags, for bit masking purposes (not a sensible state for any * individual measurement.) */ private static final int STATE_ALL = 0x3fff; // 2 bits + 4 bits + 4 bits + 4 bits = 14 bits /** * The state of the 'Accumulated Delta Range' is invalid or unknown. */ public static final int ADR_STATE_UNKNOWN = 0; /** * The state of the 'Accumulated Delta Range' is valid. */ public static final int ADR_STATE_VALID = (1<<0); /** * The state of the 'Accumulated Delta Range' has detected a reset. */ public static final int ADR_STATE_RESET = (1<<1); /** * The state of the 'Accumulated Delta Range' has a cycle slip detected. */ public static final int ADR_STATE_CYCLE_SLIP = (1<<2); /** * All the 'Accumulated Delta Range' flags. */ private static final int ADR_ALL = ADR_STATE_VALID | ADR_STATE_RESET | ADR_STATE_CYCLE_SLIP; // End enumerations in sync with gps.h /** * @hide */ @TestApi public GnssMeasurement() { initialize(); } /** * Sets all contents to the values stored in the provided object. * @hide */ @TestApi public void set(GnssMeasurement measurement) { mFlags = measurement.mFlags; mSvid = measurement.mSvid; mConstellationType = measurement.mConstellationType; mTimeOffsetNanos = measurement.mTimeOffsetNanos; mState = measurement.mState; mReceivedSvTimeNanos = measurement.mReceivedSvTimeNanos; mReceivedSvTimeUncertaintyNanos = measurement.mReceivedSvTimeUncertaintyNanos; mCn0DbHz = measurement.mCn0DbHz; mPseudorangeRateMetersPerSecond = measurement.mPseudorangeRateMetersPerSecond; mPseudorangeRateUncertaintyMetersPerSecond = measurement.mPseudorangeRateUncertaintyMetersPerSecond; mAccumulatedDeltaRangeState = measurement.mAccumulatedDeltaRangeState; mAccumulatedDeltaRangeMeters = measurement.mAccumulatedDeltaRangeMeters; mAccumulatedDeltaRangeUncertaintyMeters = measurement.mAccumulatedDeltaRangeUncertaintyMeters; mCarrierFrequencyHz = measurement.mCarrierFrequencyHz; mCarrierCycles = measurement.mCarrierCycles; mCarrierPhase = measurement.mCarrierPhase; mCarrierPhaseUncertainty = measurement.mCarrierPhaseUncertainty; mMultipathIndicator = measurement.mMultipathIndicator; mSnrInDb = measurement.mSnrInDb; } /** * Resets all the contents to its original state. * @hide */ @TestApi public void reset() { initialize(); } /** * Gets the satellite ID. * *
Interpretation depends on {@link #getConstellationType()}. * See {@link GnssStatus#getSvid(int)}. */ public int getSvid() { return mSvid; } /** * Sets the Satellite ID. * @hide */ @TestApi public void setSvid(int value) { mSvid = value; } /** * Gets the constellation type. * *
The return value is one of those constants with {@code CONSTELLATION_} prefix in * {@link GnssStatus}. */ @GnssStatus.ConstellationType public int getConstellationType() { return mConstellationType; } /** * Sets the constellation type. * @hide */ @TestApi public void setConstellationType(@GnssStatus.ConstellationType int value) { mConstellationType = value; } /** * Gets the time offset at which the measurement was taken in nanoseconds. * *
The reference receiver's time from which this is offset is specified by * {@link GnssClock#getTimeNanos()}. * *
The sign of this value is given by the following equation: *
* measurement time = TimeNanos + TimeOffsetNanos* *
The value provides an individual time-stamp for the measurement, and allows sub-nanosecond * accuracy. */ public double getTimeOffsetNanos() { return mTimeOffsetNanos; } /** * Sets the time offset at which the measurement was taken in nanoseconds. * @hide */ @TestApi public void setTimeOffsetNanos(double value) { mTimeOffsetNanos = value; } /** * Gets per-satellite sync state. * *
It represents the current sync state for the associated satellite. * *
This value helps interpret {@link #getReceivedSvTimeNanos()}. */ public int getState() { return mState; } /** * Sets the sync state. * @hide */ @TestApi public void setState(int value) { mState = value; } /** * Gets a string representation of the 'sync state'. * *
For internal and logging use only. */ private String getStateString() { if (mState == STATE_UNKNOWN) { return "Unknown"; } StringBuilder builder = new StringBuilder(); if ((mState & STATE_CODE_LOCK) != 0) { builder.append("CodeLock|"); } if ((mState & STATE_BIT_SYNC) != 0) { builder.append("BitSync|"); } if ((mState & STATE_SUBFRAME_SYNC) != 0) { builder.append("SubframeSync|"); } if ((mState & STATE_TOW_DECODED) != 0) { builder.append("TowDecoded|"); } if ((mState & STATE_MSEC_AMBIGUOUS) != 0) { builder.append("MsecAmbiguous|"); } if ((mState & STATE_SYMBOL_SYNC) != 0) { builder.append("SymbolSync|"); } if ((mState & STATE_GLO_STRING_SYNC) != 0) { builder.append("GloStringSync|"); } if ((mState & STATE_GLO_TOD_DECODED) != 0) { builder.append("GloTodDecoded|"); } if ((mState & STATE_BDS_D2_BIT_SYNC) != 0) { builder.append("BdsD2BitSync|"); } if ((mState & STATE_BDS_D2_SUBFRAME_SYNC) != 0) { builder.append("BdsD2SubframeSync|"); } if ((mState & STATE_GAL_E1BC_CODE_LOCK) != 0) { builder.append("GalE1bcCodeLock|"); } if ((mState & STATE_GAL_E1C_2ND_CODE_LOCK) != 0) { builder.append("E1c2ndCodeLock|"); } if ((mState & STATE_GAL_E1B_PAGE_SYNC) != 0) { builder.append("GalE1bPageSync|"); } if ((mState & STATE_SBAS_SYNC) != 0) { builder.append("SbasSync|"); } int remainingStates = mState & ~STATE_ALL; if (remainingStates > 0) { builder.append("Other("); builder.append(Integer.toBinaryString(remainingStates)); builder.append(")|"); } builder.setLength(builder.length() - 1); return builder.toString(); } /** * Gets the received GNSS satellite time, at the measurement time, in nanoseconds. * *
For GPS & QZSS, this is: *
Given the highest sync state that can be achieved, per each satellite, valid range * for this field can be: *
* Searching : [ 0 ] : STATE_UNKNOWN * C/A code lock : [ 0 1ms ] : STATE_CODE_LOCK is set * Bit sync : [ 0 20ms ] : STATE_BIT_SYNC is set * Subframe sync : [ 0 6s ] : STATE_SUBFRAME_SYNC is set * TOW decoded : [ 0 1week ] : STATE_TOW_DECODED is set* *
Note well: if there is any ambiguity in integer millisecond, {@code STATE_MSEC_AMBIGUOUS} * should be set accordingly, in the 'state' field. * *
This value must be populated if 'state' != {@code STATE_UNKNOWN}. * *
For Glonass, this is: *
Given the highest sync state that can be achieved, per each satellite, valid range for * this field can be: *
* Searching : [ 0 ] : STATE_UNKNOWN * C/A code lock : [ 0 1ms ] : STATE_CODE_LOCK is set * Symbol sync : [ 0 10ms ] : STATE_SYMBOL_SYNC is set * Bit sync : [ 0 20ms ] : STATE_BIT_SYNC is set * String sync : [ 0 2s ] : STATE_GLO_STRING_SYNC is set * Time of day : [ 0 1day ] : STATE_GLO_TOD_DECODED is set* *
For Beidou, this is: *
Given the highest sync state that can be achieved, per each satellite, valid range for * this field can be: *
* Searching : [ 0 ] : STATE_UNKNOWN * C/A code lock : [ 0 1ms ] : STATE_CODE_LOCK is set * Bit sync (D2) : [ 0 2ms ] : STATE_BDS_D2_BIT_SYNC is set * Bit sync (D1) : [ 0 20ms ] : STATE_BIT_SYNC is set * Subframe (D2) : [ 0 0.6s ] : STATE_BDS_D2_SUBFRAME_SYNC is set * Subframe (D1) : [ 0 6s ] : STATE_SUBFRAME_SYNC is set * Time of week : [ 0 1week ] : STATE_TOW_DECODED is set* *
For Galileo, this is: *
* E1BC code lock : [ 0 4ms ] : STATE_GAL_E1BC_CODE_LOCK is set * E1C 2nd code lock: [ 0 100ms ] : STATE_GAL_E1C_2ND_CODE_LOCK is set * E1B page : [ 0 2s ] : STATE_GAL_E1B_PAGE_SYNC is set * Time of week : [ 0 1week ] : STATE_GAL_TOW_DECODED is set* *
For SBAS, this is: *
Given the highest sync state that can be achieved, per each satellite, valid range for * this field can be: *
* Searching : [ 0 ] : STATE_UNKNOWN * C/A code lock : [ 0 1ms ] : STATE_CODE_LOCK is set * Symbol sync : [ 0 2ms ] : STATE_SYMBOL_SYNC is set * Message : [ 0 1s ] : STATE_SBAS_SYNC is set*/ public long getReceivedSvTimeNanos() { return mReceivedSvTimeNanos; } /** * Sets the received GNSS time in nanoseconds. * @hide */ @TestApi public void setReceivedSvTimeNanos(long value) { mReceivedSvTimeNanos = value; } /** * Gets the error estimate (1-sigma) for the received GNSS time, in nanoseconds. */ public long getReceivedSvTimeUncertaintyNanos() { return mReceivedSvTimeUncertaintyNanos; } /** * Sets the received GNSS time uncertainty (1-Sigma) in nanoseconds. * @hide */ @TestApi public void setReceivedSvTimeUncertaintyNanos(long value) { mReceivedSvTimeUncertaintyNanos = value; } /** * Gets the Carrier-to-noise density in dB-Hz. * *
Typical range: 10-50 db-Hz. * *
The value contains the measured C/N0 for the signal at the antenna input. */ public double getCn0DbHz() { return mCn0DbHz; } /** * Sets the carrier-to-noise density in dB-Hz. * @hide */ @TestApi public void setCn0DbHz(double value) { mCn0DbHz = value; } /** * Gets the Pseudorange rate at the timestamp in m/s. * *
The error estimate for this value is * {@link #getPseudorangeRateUncertaintyMetersPerSecond()}. * *
The value is uncorrected, i.e. corrections for receiver and satellite clock frequency * errors are not included. * *
A positive 'uncorrected' value indicates that the SV is moving away from the receiver. The * sign of the 'uncorrected' 'pseudorange rate' and its relation to the sign of 'doppler shift' * is given by the equation: * *
* pseudorange rate = -k * doppler shift (where k is a constant)*/ public double getPseudorangeRateMetersPerSecond() { return mPseudorangeRateMetersPerSecond; } /** * Sets the pseudorange rate at the timestamp in m/s. * @hide */ @TestApi public void setPseudorangeRateMetersPerSecond(double value) { mPseudorangeRateMetersPerSecond = value; } /** * Gets the pseudorange's rate uncertainty (1-Sigma) in m/s. * *
The uncertainty is represented as an absolute (single sided) value. */ public double getPseudorangeRateUncertaintyMetersPerSecond() { return mPseudorangeRateUncertaintyMetersPerSecond; } /** * Sets the pseudorange's rate uncertainty (1-Sigma) in m/s. * @hide */ @TestApi public void setPseudorangeRateUncertaintyMetersPerSecond(double value) { mPseudorangeRateUncertaintyMetersPerSecond = value; } /** * Gets 'Accumulated Delta Range' state. * *
It indicates whether {@link #getAccumulatedDeltaRangeMeters()} is reset or there is a * cycle slip (indicating 'loss of lock'). */ public int getAccumulatedDeltaRangeState() { return mAccumulatedDeltaRangeState; } /** * Sets the 'Accumulated Delta Range' state. * @hide */ @TestApi public void setAccumulatedDeltaRangeState(int value) { mAccumulatedDeltaRangeState = value; } /** * Gets a string representation of the 'Accumulated Delta Range state'. * *
For internal and logging use only. */ private String getAccumulatedDeltaRangeStateString() { if (mAccumulatedDeltaRangeState == ADR_STATE_UNKNOWN) { return "Unknown"; } StringBuilder builder = new StringBuilder(); if ((mAccumulatedDeltaRangeState & ADR_STATE_VALID) == ADR_STATE_VALID) { builder.append("Valid|"); } if ((mAccumulatedDeltaRangeState & ADR_STATE_RESET) == ADR_STATE_RESET) { builder.append("Reset|"); } if ((mAccumulatedDeltaRangeState & ADR_STATE_CYCLE_SLIP) == ADR_STATE_CYCLE_SLIP) { builder.append("CycleSlip|"); } int remainingStates = mAccumulatedDeltaRangeState & ~ADR_ALL; if (remainingStates > 0) { builder.append("Other("); builder.append(Integer.toBinaryString(remainingStates)); builder.append(")|"); } builder.deleteCharAt(builder.length() - 1); return builder.toString(); } /** * Gets the accumulated delta range since the last channel reset, in meters. * *
The error estimate for this value is {@link #getAccumulatedDeltaRangeUncertaintyMeters()}. * *
The availability of the value is represented by {@link #getAccumulatedDeltaRangeState()}. * *
A positive value indicates that the SV is moving away from the receiver. * The sign of {@link #getAccumulatedDeltaRangeMeters()} and its relation to the sign of * {@link #getCarrierPhase()} is given by the equation: * *
* accumulated delta range = -k * carrier phase (where k is a constant)*/ public double getAccumulatedDeltaRangeMeters() { return mAccumulatedDeltaRangeMeters; } /** * Sets the accumulated delta range in meters. * @hide */ @TestApi public void setAccumulatedDeltaRangeMeters(double value) { mAccumulatedDeltaRangeMeters = value; } /** * Gets the accumulated delta range's uncertainty (1-Sigma) in meters. * *
The uncertainty is represented as an absolute (single sided) value. * *
The status of the value is represented by {@link #getAccumulatedDeltaRangeState()}. */ public double getAccumulatedDeltaRangeUncertaintyMeters() { return mAccumulatedDeltaRangeUncertaintyMeters; } /** * Sets the accumulated delta range's uncertainty (1-sigma) in meters. * *
The status of the value is represented by {@link #getAccumulatedDeltaRangeState()}. * * @hide */ @TestApi public void setAccumulatedDeltaRangeUncertaintyMeters(double value) { mAccumulatedDeltaRangeUncertaintyMeters = value; } /** * Returns {@code true} if {@link #getCarrierFrequencyHz()} is available, {@code false} * otherwise. */ public boolean hasCarrierFrequencyHz() { return isFlagSet(HAS_CARRIER_FREQUENCY); } /** * Gets the carrier frequency at which codes and messages are modulated. * *
For GPS, e.g., it can be L1 or L2. If the field is not set, it is the primary common use * frequency, e.g. L1 for GPS. * *
The value is only available if {@link #hasCarrierFrequencyHz()} is {@code true}. */ public float getCarrierFrequencyHz() { return mCarrierFrequencyHz; } /** * Sets the Carrier frequency (L1 or L2) in Hz. * @hide */ @TestApi public void setCarrierFrequencyHz(float carrierFrequencyHz) { setFlag(HAS_CARRIER_FREQUENCY); mCarrierFrequencyHz = carrierFrequencyHz; } /** * Resets the Carrier frequency (L1 or L2) in Hz. * @hide */ @TestApi public void resetCarrierFrequencyHz() { resetFlag(HAS_CARRIER_FREQUENCY); mCarrierFrequencyHz = Float.NaN; } /** * Returns {@code true} if {@link #getCarrierCycles()} is available, {@code false} otherwise. */ public boolean hasCarrierCycles() { return isFlagSet(HAS_CARRIER_CYCLES); } /** * The number of full carrier cycles between the satellite and the receiver. * *
The reference frequency is given by the value of {@link #getCarrierFrequencyHz()}. * *
The value is only available if {@link #hasCarrierCycles()} is {@code true}. */ public long getCarrierCycles() { return mCarrierCycles; } /** * Sets the number of full carrier cycles between the satellite and the receiver. * @hide */ @TestApi public void setCarrierCycles(long value) { setFlag(HAS_CARRIER_CYCLES); mCarrierCycles = value; } /** * Resets the number of full carrier cycles between the satellite and the receiver. * @hide */ @TestApi public void resetCarrierCycles() { resetFlag(HAS_CARRIER_CYCLES); mCarrierCycles = Long.MIN_VALUE; } /** * Returns {@code true} if {@link #getCarrierPhase()} is available, {@code false} otherwise. */ public boolean hasCarrierPhase() { return isFlagSet(HAS_CARRIER_PHASE); } /** * Gets the RF phase detected by the receiver. * *
Range: [0.0, 1.0]. * *
This is the fractional part of the complete carrier phase measurement. * *
The reference frequency is given by the value of {@link #getCarrierFrequencyHz()}. * *
The error estimate for this value is {@link #getCarrierPhaseUncertainty()}. * *
The value is only available if {@link #hasCarrierPhase()} is {@code true}. */ public double getCarrierPhase() { return mCarrierPhase; } /** * Sets the RF phase detected by the receiver. * @hide */ @TestApi public void setCarrierPhase(double value) { setFlag(HAS_CARRIER_PHASE); mCarrierPhase = value; } /** * Resets the RF phase detected by the receiver. * @hide */ @TestApi public void resetCarrierPhase() { resetFlag(HAS_CARRIER_PHASE); mCarrierPhase = Double.NaN; } /** * Returns {@code true} if {@link #getCarrierPhaseUncertainty()} is available, {@code false} * otherwise. */ public boolean hasCarrierPhaseUncertainty() { return isFlagSet(HAS_CARRIER_PHASE_UNCERTAINTY); } /** * Gets the carrier-phase's uncertainty (1-Sigma). * *
The uncertainty is represented as an absolute (single sided) value. * *
The value is only available if {@link #hasCarrierPhaseUncertainty()} is {@code true}. */ public double getCarrierPhaseUncertainty() { return mCarrierPhaseUncertainty; } /** * Sets the Carrier-phase's uncertainty (1-Sigma) in cycles. * @hide */ @TestApi public void setCarrierPhaseUncertainty(double value) { setFlag(HAS_CARRIER_PHASE_UNCERTAINTY); mCarrierPhaseUncertainty = value; } /** * Resets the Carrier-phase's uncertainty (1-Sigma) in cycles. * @hide */ @TestApi public void resetCarrierPhaseUncertainty() { resetFlag(HAS_CARRIER_PHASE_UNCERTAINTY); mCarrierPhaseUncertainty = Double.NaN; } /** * Gets a value indicating the 'multipath' state of the event. */ @MultipathIndicator public int getMultipathIndicator() { return mMultipathIndicator; } /** * Sets the 'multi-path' indicator. * @hide */ @TestApi public void setMultipathIndicator(@MultipathIndicator int value) { mMultipathIndicator = value; } /** * Gets a string representation of the 'multi-path indicator'. * *
For internal and logging use only.
*/
private String getMultipathIndicatorString() {
switch(mMultipathIndicator) {
case MULTIPATH_INDICATOR_UNKNOWN:
return "Unknown";
case MULTIPATH_INDICATOR_DETECTED:
return "Detected";
case MULTIPATH_INDICATOR_NOT_USED:
return "NotUsed";
default:
return " The value is only available if {@link #hasSnrInDb()} is {@code true}.
*/
public double getSnrInDb() {
return mSnrInDb;
}
/**
* Sets the Signal-to-noise ratio (SNR) in dB.
* @hide
*/
@TestApi
public void setSnrInDb(double snrInDb) {
setFlag(HAS_SNR);
mSnrInDb = snrInDb;
}
/**
* Resets the Signal-to-noise ratio (SNR) in dB.
* @hide
*/
@TestApi
public void resetSnrInDb() {
resetFlag(HAS_SNR);
mSnrInDb = Double.NaN;
}
public static final Creator