GPS Receiver User Manual

Copernicus GPS Receiver 191
TRIMBLE ASCII INTERFACE PROTOCOL (TAIP) B
Latitude and Longitude Conversion
The TAIP protocol reports latitude as positive north decimal degrees and longitude as
positive east decimal degrees, using the WGS-84 datum. For your application, you
may wish to convert to degrees, minutes and seconds. The following example
illustrates the conversion of decimal degrees to degrees, minutes and seconds.
Example
Given latitude and longitude in decimal degrees,
Latitude: +37.39438
o
Longitude: -122.03846
o
Convert latitude by multiplying the decimal fraction of degrees by 60 to convert to
minutes,
0.39438 x 60 = 23.6628 minutes
Retain the integer (23) portion as the minutes then multiply the decimal fraction by 60
to convert to seconds,
0.6628 x 60 = 39.768 seconds
Since the sign of the latitude in this example is positive the result is,
Latitude: N 37
o
23' 39.77"
The longitude is converted in the same fashion,
Longitude: W 122
o
02' 18.46"
Note – At the earth's equator, one degree of latitude and longitude represents 68.7
miles;
therefore, 0.00001 degrees represents approximately 3.6 feet or 1.1 meters. Each
second represents approximately 100.76 ft.
(30.7 m).