lejos.gps
Class SimpleGPS

java.lang.Object
  java.lang.Thread
      lejos.gps.SimpleGPS

All Implemented Interfaces:

Runnable

Direct Known Subclasses:

GPS

public class SimpleGPS
extends Thread

This class manages data received from a GPS Device. SimpleGPS Class manages the following NMEA Sentences which supply location, heading, and speed data: GPGGA (location data) GPVTG (heading and speed data)

Author:

BB

Field Summary

int	errors
protected GGASentence	ggaSentence
protected static Vector	listeners
protected VTGSentence	vtgSentence

Fields inherited from class java.lang.Thread

MAX_PRIORITY, MIN_PRIORITY, NORM_PRIORITY

Constructor Summary

SimpleGPS(InputStream in)
The constructor.

Method Summary

static void	addListener(GPSListener listener) add a listener to manage events with GPS
void	close() Method used to close connection.
float	getAltitude() The altitude above mean sea level
float	getCourse() Get the course heading of the GPS unit.
int	getFixMode() Fix quality: 0 = invalid 1 = GPS fix (SPS) 2 = DGPS fix 3 = PPS fix 4 = Real Time Kinematic 5 = Float RTK 6 = estimated (dead reckoning) (2.3 feature) 7 = Manual input mode 8 = Simulation mode
int	getFixType() 3D fix - values include: 1 = no fix 2 = 2D fix 3 = 3D fix
float	getHDOP() Get the Horizontal Dilution of Precision (HDOP).
double	getLatitude() Get Latitude
char	getLatitudeDirection() Get Latitude Direction
double	getLongitude() Get Longitude
char	getLongitudeDirection() Get Longitude Direction
float	getPDOP() Get the 3D Position Dilution of Precision (PDOP).
int[]	getPRN() Get an Array of Pseudo-Random Noise codes (PRN).
int	getSatellitesTracked() Returns the number of satellites being tracked to determine the coordinates.
String	getSelectionType() Selection type of 2D or 3D fix 'M' = manual 'A' = automatic
float	getSpeed() Get speed in kilometers per hour
int	getTimeStamp() Get the last time stamp from the satellite for GGA sentence.
float	getVDOP() Get the Vertical Dilution of Precision (VDOP).
protected static void	notifyListeners(NMEASentence sen)
static void	removeListener(GPSListener listener) Remove a listener
void	run() Keeps reading sentences from GPS receiver stream and extracting data.
protected void	sentenceChooser(String token, String s) Internal helper method to aid in the subclass architecture.

Methods inherited from class java.lang.Thread

currentThread, getPriority, interrupt, interrupted, isAlive, isDaemon, isInterrupted, join, join, setDaemon, setPriority, sleep, start, yield

Methods inherited from class java.lang.Object

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

Field Detail

errors

public int errors

ggaSentence

protected GGASentence ggaSentence

vtgSentence

protected VTGSentence vtgSentence

listeners

protected static Vector listeners

Constructor Detail

SimpleGPS

public SimpleGPS(InputStream in)

The constructor. It needs an InputStream

Parameters:

in - An input stream from the GPS receiver

Method Detail

getLatitude

public double getLatitude()

Get Latitude

Returns:

the latitude

getLatitudeDirection

public char getLatitudeDirection()

Get Latitude Direction

Returns:

the latitude direction

getLongitude

public double getLongitude()

Get Longitude

Returns:

the longitude

getLongitudeDirection

public char getLongitudeDirection()

Get Longitude Direction

Returns:

the longitude direction

getAltitude

public float getAltitude()

The altitude above mean sea level

Returns:

Meters above sea level e.g. 545.4

getSatellitesTracked

public int getSatellitesTracked()

Returns the number of satellites being tracked to determine the coordinates.

Returns:

Number of satellites e.g. 8

getFixMode

public int getFixMode()

Fix quality:

0 = invalid

1 = GPS fix (SPS)

2 = DGPS fix

3 = PPS fix

4 = Real Time Kinematic

5 = Float RTK

6 = estimated (dead reckoning) (2.3 feature)

7 = Manual input mode

8 = Simulation mode

Returns:

the fix quality

getTimeStamp

public int getTimeStamp()

Get the last time stamp from the satellite for GGA sentence.

Returns:

Time as a UTC integer. 123459 = 12:34:59 UTC

getSpeed

public float getSpeed()

Get speed in kilometers per hour

Returns:

the speed in kilometers per hour

getCourse

public float getCourse()

Get the course heading of the GPS unit.

Returns:

course (0.0 to 360.0)

getSelectionType

public String getSelectionType()

Selection type of 2D or 3D fix

'M' = manual

'A' = automatic

Returns:

selection type - either 'A' or 'M'

getFixType

public int getFixType()

3D fix - values include:

1 = no fix

2 = 2D fix

3 = 3D fix

Returns:

fix type (1 to 3)

getPRN

public int[] getPRN()

Get an Array of Pseudo-Random Noise codes (PRN). You can look up a list of GPS satellites by this number at: http://en.wikipedia.org/wiki/List_of_GPS_satellite_launches Note: This number might be similar or identical to SVN.

Returns:

array of PRNs

getPDOP

public float getPDOP()

Get the 3D Position Dilution of Precision (PDOP). When visible GPS satellites are close together in the sky, the geometry is said to be weak and the DOP value is high; when far apart, the geometry is strong and the DOP value is low. Thus a low DOP value represents a better GPS positional accuracy due to the wider angular separation between the satellites used to calculate a GPS unit's position. Other factors that can increase the effective DOP are obstructions such as nearby mountains or buildings.

Returns:

The PDOP (PDOP * 6 meters = the error to expect in meters) -1 means PDOP is unavailable from the GPS.

getHDOP

public float getHDOP()

Get the Horizontal Dilution of Precision (HDOP). When visible GPS satellites are close together in the sky, the geometry is said to be weak and the DOP value is high; when far apart, the geometry is strong and the DOP value is low. Thus a low DOP value represents a better GPS positional accuracy due to the wider angular separation between the satellites used to calculate a GPS unit's position. Other factors that can increase the effective DOP are obstructions such as nearby mountains or buildings.

Returns:

the HDOP (HDOP * 6 meters = the error to expect in meters) -1 means HDOP is unavailable from the GPS.

getVDOP

public float getVDOP()

Get the Vertical Dilution of Precision (VDOP). When visible GPS satellites are close together in the sky, the geometry is said to be weak and the DOP value is high; when far apart, the geometry is strong and the DOP value is low. Thus a low DOP value represents a better GPS positional accuracy due to the wider angular separation between the satellites used to calculate a GPS unit's position. Other factors that can increase the effective DOP are obstructions such as nearby mountains or buildings.

Returns:

the VDOP (VDOP * 6 meters = the error to expect in meters) -1 means VDOP is unavailable from the GPS.

close

public void close()
           throws IOException

Method used to close connection. There is no real need to call this method. Included in case programmer wants absolutely clean exit.

Throws:

IOException

run

public void run()

Keeps reading sentences from GPS receiver stream and extracting data. This is a daemon thread so when program ends it won't keep running.

Specified by:

run in interface Runnable

Overrides:

run in class Thread

sentenceChooser

protected void sentenceChooser(String token,
                               String s)

Internal helper method to aid in the subclass architecture. Overwritten by subclass.

Parameters:

token -

s -

notifyListeners

protected static void notifyListeners(NMEASentence sen)

addListener

public static void addListener(GPSListener listener)

add a listener to manage events with GPS

Parameters:

listener -

removeListener

public static void removeListener(GPSListener listener)

Remove a listener

Parameters:

listener -