2
votes
1answer
247 views

Current time from GPRMC or GPZDA?

In GPRMC there is a time field, called fix time. Can I consider this always the same as value from GPZDA time? Is there any possibility that when GPS device is configured to stream both GPRMC and ...
2
votes
0answers
94 views

How to configure various client applications to display AVL data?

Given x number of GPS units transmitting NMEA formatted strings back to a server (xxx.xxx.xxx.xxx:xxxxx) is there a way to listen in on the traffic and parse NMEA formatted strings for display on a ...
12
votes
3answers
1k views

GPS Tracking by SMS

I have a GPS Tracker which sends the GPRMC string of the NMEA 0183 protocol, at fixed periodicity, to a predefined number as SMS. I am looking for a software which can port these incoming SMS to a COM ...
17
votes
6answers
1k views

How correct is the “Accuracy” value given by GPS devices?

I have a Garmin Forerunner 305 and a Google Nexus One Android phone. From the GPS on both these devices I can get a "Accuracy" value that is usually between 6-20 meters. How much can I trust this ...
5
votes
1answer
546 views

Calculating absolute precision confidence number from Dilution of Precision indicators from GPS receiver

End-user GPS receivers typically show an absolute confidence indication, such as Within 25 Metres, for the calculated position. I am parsing NMEA data from a GPS unit and wan't to calculate a similar ...