Xylem SonTek River Surveyor M9, Системное руководство

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SonTek, a Xylem brand
104 RiverSurveyor S5/M9 System Manual (February 2013)
Table 4: HDOP Value Descriptions
HDOP
Value
Rating Description
1 Ideal
This is the highest possible confidence level to be used for applications de-
manding the highest possible precision at all times.
2-3 Excellent
At this confidence level, positional measurements are considered accurate
enough to meet all but the most sensitive applications.
4-6 Good
Represents a level that marks the minimum appropriate for making a good-
quality discharge measurement. Positional measurements could be used to
make reliable in-route navigation suggestions to the user.
7-8 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.
9-20 Fair
Represents a low confidence level. Positional measurements should be dis-
carded or used only to indicate a very rough estimate of the current location.
21-50 Poor
At this level, measurements are inaccurate by as much as 300 meters with a
6 meter accurate device (50 DOP x 6 meters) and should be discarded.
e. RTK
a) Be sure the SS antenna is connected to the RTK Base Station
b) Be sure the battery pack in the RTK Base Station is fully charged
c) Be sure the RTK Base Station is within the 1 mile range limit of the ADP
d) The GPS antennas should be mounted to the RTK Base Station and ADP.
e) Connect time for Differential Quality GPS data is approximately 5 minutes
f) Connect time for RTK quality GPS data is approximately 10 minutes
g) Use the status icons to evaluate GPS (RTK and DGPS) Communications Quality.
The tables below provide a quick reference for the software status icons and the
LEDs on the PCM and RTK Base Station.