4RF Aprisa SRi, User Manual

Page: 104 / 353

104 | Managing the Radio
Aprisa SRi User Manual 1.1.0
GPS Receiver ’ on page 145).
The GPS Horizontal Dilution Of Precision (HDOP) information provides a GPS signal quality rating;
DOP Value Rating Description
< 1 Ideal Highest possible confidence level to be used for applications demanding
the highest possible precision at all times.
1-2 Excellent At this confidence level, positional measurements are considered
accurate enough to meet all but the most sensitive applications.
2-5 Good Represents a level that marks the minimum appropriate for making
business decisions. Positional measurements could be used to make
reliable in-route navigation suggestions to the user.
5-10 Moderate
Positional measurements could be used for calculations, but the fix
quality could still be improved. A more open view of the sky is
recommended.
10-20 Fair Represents a low confidence level. Positional measurements should be
discarded or used only to indicate a very rough estimate of the current
location.
>20 Poor At this level, measurements are inaccurate by as much as 300 meters with
a 6-meter accurate device (50 DOP × 6 meters) and should be discarded.
Controls
The Update GPS button updates the GPS Coordinates field from the installed USB GPS Receiver.
If the GPS Receiver is enabled but is not operating or not receiving a valid GPS signal, the GPS Status will
show ‘Update Failed’.