org.orekit.time

Class GNSSDate

java.lang.Object

org.orekit.time.GNSSDate

All Implemented Interfaces:

Serializable, TimeStamped

public class GNSSDate
extends Object
implements Serializable, TimeStamped

Container for date in GNSS form.

This class can be used to handle GPS, Galileo, BeiDou and QZSS dates.

Author:

Luc Maisonobe (original code), Bryan Cazabonne (generalization to all GNSS constellations)

See Also:

AbsoluteDate, Serialized Form

Constructor Summary

Constructors

Constructor and Description
GNSSDate(AbsoluteDate date, SatelliteSystem system) Build an instance from an absolute date.
GNSSDate(int weekNumber, double milliInWeek, SatelliteSystem system) Build an instance corresponding to a GNSS date.

Method Summary

Modifier and Type	Method and Description
AbsoluteDate	getDate() Get the date.
double	getMilliInWeek() Get the number of milliseconds since week start.
static DateComponents	getRolloverReference() Get the reference date ensuring continuity across GNSS week rollover.
int	getWeekNumber() Get the week number since the GNSS reference epoch.
static void	setRolloverReference(DateComponents reference) Set a reference date for ensuring continuity across GNSS week rollover.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

GNSSDate

public GNSSDate(int weekNumber,
                double milliInWeek,
                SatelliteSystem system)

Build an instance corresponding to a GNSS date.

GNSS dates are provided as a week number starting at the GNSS reference epoch and as a number of milliseconds since week start.

Many interfaces provide week number modulo the constellation week cycle. In order to cope with this, when the week number is smaller than the week cycle, this constructor assumes a modulo operation has been performed and it will fix the week number according to the reference date set up for handling rollover (see setRolloverReference(reference)). If the week number is equal to the week cycle or larger, it will be used without any correction.

Parameters:

weekNumber - week number

milliInWeek - number of milliseconds since week start

system - satellite system to consider

GNSSDate

public GNSSDate(AbsoluteDate date,
                SatelliteSystem system)

Build an instance from an absolute date.

Parameters:

date - absolute date to consider

system - satellite system to consider

Method Detail

setRolloverReference

public static void setRolloverReference(DateComponents reference)

Set a reference date for ensuring continuity across GNSS week rollover.

Instance created using the GNSSDate(weekNumber, milliInWeek, system) constructor and with a week number between 0 and the constellation week cycle (cycleW) after this method has been called will fix the week number to ensure they correspond to dates between reference - cycleW / 2 weeks and reference + cycleW / 2 weeks.

If this method is never called, a default reference date for rollover will be set using the date of the last known EOP entry retrieved from UT1 time scale.

Parameters:

reference - reference date for GNSS week rollover

Since:

9.3.1

See Also:

getRolloverReference(), GNSSDate(int, double, SatelliteSystem)

getRolloverReference

public static DateComponents getRolloverReference()

Get the reference date ensuring continuity across GNSS week rollover.

Returns:

reference reference date for GNSS week rollover

Since:

9.3.1

See Also:

setRolloverReference(DateComponents), GNSSDate(int, double, SatelliteSystem)

getWeekNumber

public int getWeekNumber()

Get the week number since the GNSS reference epoch.

The week number returned here has been fixed for GNSS week rollover, i.e. it may be larger than the corresponding week cycle of the constellation.

Returns:

week number since since the GNSS reference epoch

getMilliInWeek

public double getMilliInWeek()

Get the number of milliseconds since week start.

Returns:

number of milliseconds since week start

getDate

public AbsoluteDate getDate()

Get the date.

Specified by:

getDate in interface TimeStamped

Returns:

date attached to the object