Measurement Precision And Position Accuracy - Leica GM30 User Manual

GPS Carrier tracking
GPS code
measurements
9.1.2

GNSS
measurements
Accuracy (rms)
single receiver
navigation mode
Accuracy in
differential code
mode
GR30/GM30/GR50, Technical Data
Condition
L1, AS off or on
L2, AS off
L2, AS on
Condition
L1, AS off
L1, AS on
L2, AS off
L2, AS on
Code smoothing using carrier phase measurements is optional.

Measurement Precision and Position Accuracy

Measurement precision, accuracy in position and height, reliability and time for initial-
isation are dependent upon various factors including the number of satellites tracked,
the observation time, the ephemeris accuracy, the atmospheric conditions, multipath
and resolved ambiguities. Figures quoted assume normal to favourable conditions.
The following accuracies, given as root mean square (rms), are based on measure-
ments processed using receiver firmware, LEICA Geo Office and the Bernese Software.
The use of multiple GNSS systems can increase accuracy by up to 30% relative to GPS
only.
Fully independent code and phase measurements of all frequencies.
1
Precision GPS L1/L2/L5
Resolution
1
For satellites with SNR higher than 42 dB-Hz; Galileo and BeiDou values are expected
to be similar.
Navigation accuracy 5–10 m rms for each coordinate
Degradation possible due to Selective Availability
Leica VADASE - Velocity & Displacement Engine
• Velocity accuracy: 0.003 m/s rms horizontal, 0.005 m/s rms vertical.
• Typical velocity derived displacement sensitivity: 1 cm/s horizontal, 2 cm/s vertical.
• Velocity Limit: 515 m/s.
(Export licensing restricts operation to a maximum of 515 m/s)
Typical position accuracy of a differential code solution for static and kinematic
surveys:
• SBAS (GPS-only): 0.6 m
• DGNSS: 0.25 m + 1 ppm (horizontal), 0.5 m + 1 ppm (vertical)
GR30/GM30/GR50
Reconstructed carrier phase via C/A-code.
Reconstructed carrier phase via P2-code.
Switches automatically to patented P-code aided technique
providing full L2 reconstructed carrier phase.
GR30/GM30/GR50
Code measurements: C/A-code.
Code measurements: P2-code and/or L2C code.
Code measurements: Patented P-code aided code and/or L2C
code.
Phase
0.2 mm rms
0.01 mm
Code
20 mm rms
0.0005 m
63