GnssClock

public final class GnssClock
extends Object implements Parcelable

java.lang.Object
   ↳ android.location.GnssClock


A class containing a GNSS clock timestamp.

It represents a measurement of the GNSS receiver's clock.

Summary

Inherited constants

Fields

public static final Creator<GnssClock> CREATOR

Public methods

int describeContents()

Describe the kinds of special objects contained in this Parcelable instance's marshaled representation.

double getBiasNanos()

Gets the clock's sub-nanosecond bias.

double getBiasUncertaintyNanos()

Gets the clock's Bias Uncertainty (1-Sigma) in nanoseconds.

double getDriftNanosPerSecond()

Gets the clock's Drift in nanoseconds per second.

double getDriftUncertaintyNanosPerSecond()

Gets the clock's Drift Uncertainty (1-Sigma) in nanoseconds per second.

long getElapsedRealtimeNanos()

Returns the elapsed real-time of this clock since system boot, in nanoseconds.

double getElapsedRealtimeUncertaintyNanos()

Gets the estimate of the relative precision of the alignment of the getElapsedRealtimeNanos() timestamp, with the reported measurements in nanoseconds (68% confidence).

long getFullBiasNanos()

Gets the difference between hardware clock (getTimeNanos()) inside GPS receiver and the true GPS time since 0000Z, January 6, 1980, in nanoseconds.

int getHardwareClockDiscontinuityCount()

Gets count of hardware clock discontinuities.

int getLeapSecond()

Gets the leap second associated with the clock's time.

double getReferenceCarrierFrequencyHzForIsb()

Returns the reference carrier frequency in Hz for inter-signal bias.

String getReferenceCodeTypeForIsb()

Returns the reference code type for inter-signal bias.

int getReferenceConstellationTypeForIsb()

Returns the reference constellation type for inter-signal bias.

long getTimeNanos()

Gets the GNSS receiver internal hardware clock value in nanoseconds.

double getTimeUncertaintyNanos()

Gets the clock's time Uncertainty (1-Sigma) in nanoseconds.

boolean hasBiasNanos()

Returns true if getBiasNanos() is available, false otherwise.

boolean hasBiasUncertaintyNanos()

Returns true if getBiasUncertaintyNanos() is available, false otherwise.

boolean hasDriftNanosPerSecond()

Returns true if getDriftNanosPerSecond() is available, false otherwise.

boolean hasDriftUncertaintyNanosPerSecond()

Returns true if getDriftUncertaintyNanosPerSecond() is available, false otherwise.

boolean hasElapsedRealtimeNanos()

Returns true if getElapsedRealtimeNanos() is available, false otherwise.

boolean hasElapsedRealtimeUncertaintyNanos()

Returns true if getElapsedRealtimeUncertaintyNanos() is available, false otherwise.

boolean hasFullBiasNanos()

Returns true if getFullBiasNanos() is available, false otherwise.

boolean hasLeapSecond()

Returns true if getLeapSecond() is available, false otherwise.

boolean hasReferenceCarrierFrequencyHzForIsb()

Returns true if getReferenceCarrierFrequencyHzForIsb() is available, false otherwise.

boolean hasReferenceCodeTypeForIsb()

Returns true if getReferenceCodeTypeForIsb() is available, false otherwise.

boolean hasReferenceConstellationTypeForIsb()

Returns true if getReferenceConstellationTypeForIsb() is available, false otherwise.

boolean hasTimeUncertaintyNanos()

Returns true if getTimeUncertaintyNanos() is available, false otherwise.

String toString()

Returns a string representation of the object.

void writeToParcel(Parcel parcel, int flags)

Flatten this object in to a Parcel.

Inherited methods

Fields

CREATOR

Added in API level 24
public static final Creator<GnssClock> CREATOR

Public methods

describeContents

Added in API level 24
public int describeContents ()

Describe the kinds of special objects contained in this Parcelable instance's marshaled representation. For example, if the object will include a file descriptor in the output of writeToParcel(android.os.Parcel, int), the return value of this method must include the CONTENTS_FILE_DESCRIPTOR bit.

Returns
int a bitmask indicating the set of special object types marshaled by this Parcelable object instance. Value is either 0 or CONTENTS_FILE_DESCRIPTOR

getBiasNanos

Added in API level 24
public double getBiasNanos ()

Gets the clock's sub-nanosecond bias.

See the description of how this field is part of converting from hardware clock time, to GPS time, in getFullBiasNanos().

The error estimate for the sum of this field and getFullBiasNanos() is getBiasUncertaintyNanos().

The value is only available if hasBiasNanos() is true.

Returns
double

getBiasUncertaintyNanos

Added in API level 24
public double getBiasUncertaintyNanos ()

Gets the clock's Bias Uncertainty (1-Sigma) in nanoseconds.

See the description of how this field provides the error estimate in the conversion from hardware clock time, to GPS time, in getFullBiasNanos().

The value is only available if hasBiasUncertaintyNanos() is true.

Returns
double Value is 0.0f or greater

getDriftNanosPerSecond

Added in API level 24
public double getDriftNanosPerSecond ()

Gets the clock's Drift in nanoseconds per second.

This value is the instantaneous time-derivative of the value provided by getBiasNanos().

A positive value indicates that the frequency is higher than the nominal (e.g. GPS master clock) frequency. The error estimate for this reported drift is getDriftUncertaintyNanosPerSecond().

The value is only available if hasDriftNanosPerSecond() is true.

Returns
double

getDriftUncertaintyNanosPerSecond

Added in API level 24
public double getDriftUncertaintyNanosPerSecond ()

Gets the clock's Drift Uncertainty (1-Sigma) in nanoseconds per second.

The value is only available if hasDriftUncertaintyNanosPerSecond() is true.

Returns
double Value is 0.0f or greater

getElapsedRealtimeNanos

Added in API level 29
public long getElapsedRealtimeNanos ()

Returns the elapsed real-time of this clock since system boot, in nanoseconds.

The value is only available if hasElapsedRealtimeNanos() is true.

Returns
long

getElapsedRealtimeUncertaintyNanos

Added in API level 29
public double getElapsedRealtimeUncertaintyNanos ()

Gets the estimate of the relative precision of the alignment of the getElapsedRealtimeNanos() timestamp, with the reported measurements in nanoseconds (68% confidence).

The value is only available if hasElapsedRealtimeUncertaintyNanos() is true.

Returns
double Value is 0.0f or greater

getFullBiasNanos

Added in API level 24
public long getFullBiasNanos ()

Gets the difference between hardware clock (getTimeNanos()) inside GPS receiver and the true GPS time since 0000Z, January 6, 1980, in nanoseconds.

This value is available if the receiver has estimated GPS time. If the computed time is for a non-GPS constellation, the time offset of that constellation to GPS has to be applied to fill this value. The value is only available if hasFullBiasNanos() is true.

The error estimate for the sum of this field and getBiasNanos() is getBiasUncertaintyNanos().

The sign of the value is defined by the following equation:

     local estimate of GPS time = TimeNanos - (FullBiasNanos + BiasNanos)

Returns
long

getHardwareClockDiscontinuityCount

Added in API level 24
public int getHardwareClockDiscontinuityCount ()

Gets count of hardware clock discontinuities.

When this value stays the same, vs. a value in a previously reported GnssClock, it can be safely assumed that the TimeNanos value has been derived from a clock that has been running continuously - e.g. a single continuously powered crystal oscillator, and thus the (FullBiasNanos + BiasNanos) offset can be modelled with traditional clock bias & drift models.

Each time this value changes, vs. the value in a previously reported GnssClock, that suggests the hardware clock may have experienced a discontinuity (e.g. a power cycle or other anomaly), so that any assumptions about modelling a smoothly changing (FullBiasNanos + BiasNanos) offset, and a smoothly growing (TimeNanos) between this and the previously reported GnssClock, should be reset.

Returns
int

getLeapSecond

Added in API level 24
public int getLeapSecond ()

Gets the leap second associated with the clock's time.

The sign of the value is defined by the following equation:

     UtcTimeNanos = TimeNanos - (FullBiasNanos + BiasNanos) - LeapSecond * 1,000,000,000

The value is only available if hasLeapSecond() is true.

Returns
int

getReferenceCarrierFrequencyHzForIsb

Added in API level 30
public double getReferenceCarrierFrequencyHzForIsb ()

Returns the reference carrier frequency in Hz for inter-signal bias.

The value is only available if hasReferenceCarrierFrequencyHzForIsb() is true.

Returns
double Value is 0.0 or greater

getReferenceCodeTypeForIsb

Added in API level 30
public String getReferenceCodeTypeForIsb ()

Returns the reference code type for inter-signal bias.

The value is only available if hasReferenceCodeTypeForIsb() is true.

The return value is one of those constants defined in GnssMeasurement#getCodeType().

Returns
String This value cannot be null.

getReferenceConstellationTypeForIsb

Added in API level 30
public int getReferenceConstellationTypeForIsb ()

Returns the reference constellation type for inter-signal bias.

The value is only available if hasReferenceConstellationTypeForIsb() is true.

The return value is one of those constants with CONSTELLATION_ prefix in GnssStatus.

Returns
int Value is GnssStatus.CONSTELLATION_UNKNOWN, GnssStatus.CONSTELLATION_GPS, GnssStatus.CONSTELLATION_SBAS, GnssStatus.CONSTELLATION_GLONASS, GnssStatus.CONSTELLATION_QZSS, GnssStatus.CONSTELLATION_BEIDOU, GnssStatus.CONSTELLATION_GALILEO, or GnssStatus.CONSTELLATION_IRNSS

getTimeNanos

Added in API level 24
public long getTimeNanos ()

Gets the GNSS receiver internal hardware clock value in nanoseconds.

This value is expected to be monotonically increasing while the hardware clock remains powered on. For the case of a hardware clock that is not continuously on, see the getHardwareClockDiscontinuityCount() field. The GPS time can be derived by subtracting the sum of getFullBiasNanos() and getBiasNanos() (when they are available) from this value. Sub-nanosecond accuracy can be provided by means of getBiasNanos().

The error estimate for this value (if applicable) is getTimeUncertaintyNanos().

Returns
long

getTimeUncertaintyNanos

Added in API level 24
public double getTimeUncertaintyNanos ()

Gets the clock's time Uncertainty (1-Sigma) in nanoseconds.

The uncertainty is represented as an absolute (single sided) value.

The value is only available if hasTimeUncertaintyNanos() is true.

This value is often effectively zero (it is the reference clock by which all other times and time uncertainties are measured), and thus this field may often be 0, or not provided.

Returns
double Value is 0.0f or greater

hasBiasNanos

Added in API level 24
public boolean hasBiasNanos ()

Returns true if getBiasNanos() is available, false otherwise.

Returns
boolean

hasBiasUncertaintyNanos

Added in API level 24
public boolean hasBiasUncertaintyNanos ()

Returns true if getBiasUncertaintyNanos() is available, false otherwise.

Returns
boolean

hasDriftNanosPerSecond

Added in API level 24
public boolean hasDriftNanosPerSecond ()

Returns true if getDriftNanosPerSecond() is available, false otherwise.

Returns
boolean

hasDriftUncertaintyNanosPerSecond

Added in API level 24
public boolean hasDriftUncertaintyNanosPerSecond ()

Returns true if getDriftUncertaintyNanosPerSecond() is available, false otherwise.

Returns
boolean

hasElapsedRealtimeNanos

Added in API level 29
public boolean hasElapsedRealtimeNanos ()

Returns true if getElapsedRealtimeNanos() is available, false otherwise.

Returns
boolean

hasElapsedRealtimeUncertaintyNanos

Added in API level 29
public boolean hasElapsedRealtimeUncertaintyNanos ()

Returns true if getElapsedRealtimeUncertaintyNanos() is available, false otherwise.

Returns
boolean

hasFullBiasNanos

Added in API level 24
public boolean hasFullBiasNanos ()

Returns true if getFullBiasNanos() is available, false otherwise.

Returns
boolean

hasLeapSecond

Added in API level 24
public boolean hasLeapSecond ()

Returns true if getLeapSecond() is available, false otherwise.

Returns
boolean

hasReferenceCarrierFrequencyHzForIsb

Added in API level 30
public boolean hasReferenceCarrierFrequencyHzForIsb ()

Returns true if getReferenceCarrierFrequencyHzForIsb() is available, false otherwise.

Returns
boolean

hasReferenceCodeTypeForIsb

Added in API level 30
public boolean hasReferenceCodeTypeForIsb ()

Returns true if getReferenceCodeTypeForIsb() is available, false otherwise.

Returns
boolean

hasReferenceConstellationTypeForIsb

Added in API level 30
public boolean hasReferenceConstellationTypeForIsb ()

Returns true if getReferenceConstellationTypeForIsb() is available, false otherwise.

Returns
boolean

hasTimeUncertaintyNanos

Added in API level 24
public boolean hasTimeUncertaintyNanos ()

Returns true if getTimeUncertaintyNanos() is available, false otherwise.

Returns
boolean

toString

Added in API level 24
public String toString ()

Returns a string representation of the object.

Returns
String a string representation of the object.

writeToParcel

Added in API level 24
public void writeToParcel (Parcel parcel, 
                int flags)

Flatten this object in to a Parcel.

Parameters
parcel Parcel: The Parcel in which the object should be written. This value cannot be null.

flags int: Additional flags about how the object should be written. May be 0 or Parcelable.PARCELABLE_WRITE_RETURN_VALUE. Value is either 0 or a combination of Parcelable.PARCELABLE_WRITE_RETURN_VALUE, and android.os.Parcelable.PARCELABLE_ELIDE_DUPLICATES