GPS information in logs

You can save the information from a GPS device to a shapefile or geodatabase feature class. You can write individual points to the log or stream data. When streaming data, you can also filter the data by properties such as time or distance. To write data to a log, you must first either create a new log or open an existing log and append locations to it.

The log has the same spatial reference as the GPS device. Besides the actual coordinate values, you can save related information to the log’s attribute table.

The following are descriptions of the fields you can save to the log:

Field

Description

Latitude

The latitude value of the position.

Longitude

The longitude value of the position.

Altitude

The altitude of the position. The unit of measure is set in Display Properties.

Date_time

The date and time of day of the position.

Date

The date of the position.

Time

The time of day of the position. If the log file is a shapefile, this field is written as a string type field using the time format specified in Windows Control Panel.

Speed_KPH

The speed in kilometers per hour of the position. This is calculated using the coordinates and the date_time information of the current and previous positions.

Heading

The direction in degrees as measured east of north of the current position. This is calculated using the previous position's coordinate.

HDOP

The horizontal dilution of precision of the position. It reflects the effect of the current geometric satellite distribution.

VDOP

The vertical dilution of precision of the position. It reflects the effect of the current geometric satellite distribution.

PDOP

The positional dilution of precision of the position. This is a combination of the HDOP and VDOP and reflects the effect of the current geometric satellite distribution.

DGPS_ID

The identification of the differential GPS unit.

DGPS_age

The length of time since the last contact with the DGPS base station.

Magnet_var

The magnetic variation of the position in degrees.

Numof_sats

The number of satellites used to calculate the position.

Avgsat_SNR

The average satellite signal-to-noise ratio.

Sats_inuse

The number of satellites in use for the position.

Quality

Quality indicator of the position.

Fields and descriptions that can be saved to the log

Related Topics

2/10/2012