Sensors & Software Inc. NG250 ユーザーズマニュアル
Noggin
12-Survey & Map Mode
103
12.3.5 GPS Parameters
The Global Positioning System (GPS) uses special satellites around the Earth to determine the
position of a GPS receiver located at any position on the surface of the Earth. GPS receivers can
be purchased from a number of manufacturers.
position of a GPS receiver located at any position on the surface of the Earth. GPS receivers can
be purchased from a number of manufacturers.
The DVL has a serial port on the back for attaching a GPS receiver. This port will accommodate
any GPS receiver that has a standard serial port output.
any GPS receiver that has a standard serial port output.
The GPS receiver can be set up to send one or more types of data strings to the DVL. These
strings are called NMEA-0183 strings and each contains positional or other information in
specific formats. Each type of string is specified by a 5-character prefix. There are numerous
NMEA strings but to integrate the GPS data into the Noggin data, the GPS must be sending at
least one of the following NMEA strings: GPGGA, GPGLL and GPRMC.
strings are called NMEA-0183 strings and each contains positional or other information in
specific formats. Each type of string is specified by a 5-character prefix. There are numerous
NMEA strings but to integrate the GPS data into the Noggin data, the GPS must be sending at
least one of the following NMEA strings: GPGGA, GPGLL and GPRMC.
This feature allows GPS information to be logged while collecting Noggin data. The GPS
information may be useful for mapping where GPR surveys have been performed (see Reading
per Trace mode below) or determining where a specific target of interest is located in GPS co-
ordinates (see Fiducial Tagging mode below).
information may be useful for mapping where GPR surveys have been performed (see Reading
per Trace mode below) or determining where a specific target of interest is located in GPS co-
ordinates (see Fiducial Tagging mode below).
The DVL can be set up to read and log GPS information collected during data acquisition with the
Noggin system. GPS information can be logged in two different ways:
1)
For every trace collected by the Noggin system, or
2)
Every time the user adds a fiducial to the data by pressing the A button (see Fiducial
Markers on page 72).
Markers on page 72).
This feature provides a means of logging GPS information to an independent file. Note that the
GPS information is NOT automatically integrated with the Noggin data. After data
acquisition is complete, the data can be downloaded to a PC and the EKKO_View Deluxe
software can be used to integrate the GPS data with the Noggin
GPS information is NOT automatically integrated with the Noggin data. After data
acquisition is complete, the data can be downloaded to a PC and the EKKO_View Deluxe
software can be used to integrate the GPS data with the Noggin
data.
In order for the DVL to read the GPS data string, the GPS settings for the specific GPS receiver
being used must be input into this menu. There are 4 important items that must be specified
correctly for the DVL to display the GPS strings. These items are Baud Rate, Stop Bits, Data Bits
and Parity. These are discussed in more detail below. The default values listed below are the
values that are typically used. Read the GPS Receiver User’s Guide or experiment with the
settings to find the correct ones.
being used must be input into this menu. There are 4 important items that must be specified
correctly for the DVL to display the GPS strings. These items are Baud Rate, Stop Bits, Data Bits
and Parity. These are discussed in more detail below. The default values listed below are the
values that are typically used. Read the GPS Receiver User’s Guide or experiment with the
settings to find the correct ones.
Once these 4 items are set correctly you should be able to run System Test #1 and have GPS
information written to the screen.
information written to the screen.
When the logging of GPS information is enabled, during data acquisition a message will appear
in the bottom left-hand corner of the DVL screen indicating whether GPS data is successfully
being received (see Section 12.2.4: P.72).
in the bottom left-hand corner of the DVL screen indicating whether GPS data is successfully
being received (see Section 12.2.4: P.72).