Positioning in Polar Grit X2 Pro/Ignite 3/Vantage V3
The Polar Grit X2 Pro/Ignite 3/Vantage V3 has built-in GPS (GNSS) that provides speed, pace, distance and altitude measurement for a range of outdoor sports, and allows you to see your route on map in the Flow app and web service after your session. The watch uses GPS, GLONASS, Galileo, BeiDou and QZSS systems simultaneously for maximum accuracy around the globe. By default, the watch also utilizes dual-frequency GPS for improved positioning accuracy especially in difficult use conditions. Alternatively, you can use a power-saving single-frequency GPS mode on your watch. Single-frequency GPS mode does not give as accurate results in difficult use conditions, but it will improve the battery lifetime during exercise. The setting is located in General settings > Positioning satellites. Choose Better accuracy (dual-frequency GPS) or Power save (single-frequency GPS).
The power save options on your watch allow you to extend your training time, for example, by changing the GPS recording rate to a less frequent interval (from 1 second to 1 minute or 2 minutes). Note that changing the GPS recording rate to a less frequent interval may result in less accurate speed/pace, distance, and route tracking.
The satellite fix requires four or more satellites. After the fix, the number of satellites will increase as more are found. The theoretical maximum number of satellites that can be used for position calculation is 64. The number of satellites in the fix is easier to increase when using A-GPS. When the fix is complete and the training session has been started, the watch attempts to add more satellites to the calculation on the go.
What is A-GPS (Assisted GPS)?
The A-GPS data tells your watch the predicted positions of the GPS, Glonass, Galileo, BeiDou and QZSS satellites. This way the watch knows where to search for the satellites and thus makes defining your initial location faster and improves the accuracy of the positioning data.
The A-GPS data updates once a day. The latest A-GPS data file is automatically updated to your watch each time you sync it with the Flow web service via FlowSync software or via the Flow app.
The A-GPS data file is valid for up to 14 days. Positioning accuracy is relatively high during the first three days, and progressively decreases during the remaining days. Regular updates help to ensure a fast satellite fix.
How to keep the A-GPS data up to date?
You can check the expiry date for the current A-GPS data file from your Polar device. Go to Settings > General settings > About your watch > Assisted GPS updated with each sync. Valid until: XX/XX/XXXX. If the data file has expired, sync your watch with the Flow web service via FlowSync software or with the Flow app to update A-GPS data. Once the A-GPS data file has expired, more time may be required for acquiring the current position.
