Survey Comparison using GNSS and
ME5000 for One kilometer Range
S.Matsui, H.Kimura (RIKEN)
1.
2.
3.
4.
5.
6.
Static Relative Positioning
Measurement of GPS Antenna Center
Survey of Reference points around the storage ring
Measurement of the distances 100m-1km
Correction by water vapor pressure
Summary
Static Relative Positioning
Phase measurement
Wavelength
190mm(L1 1.58GHz)
244mm(L2 1.23GHz)
Carrier phase precision:0.1mm
(Topcon NET G3)
1 degree=0.5mm
0.2 degree=0.1mm
Distribution of 1 minute data
401.84
1 min ×　60 = 1 hour
Sampling rate =1 Hz
Base point SR9
Rover SR4
401.835
5 mm
NS(m)
401.83
401.825
401.82
401.815
478.22
478.225
478.23
478.235
EW(m)
478.24
478.245
Measurement of Antenna Center
Sampling 1Hz
1 point=1 hour
Total 49Hours(2 Days)
G2 Position
-0.0825
-0.083
Minimum Angle
=15 degree
rms(EW)=0.49mm
rms(NS)=0.48mm
NS (m)
-0.0835
-0.084
-0.0845
-0.085
0.5mm
-0.0855
0.895
0.8955
0.896
0.8965
EW (m)
0.897
0.8975
0.898
Minimum Elevation Angle vs Distribution
rms (mm)
4
3
2
rms EW
rms NS
1
0
5 10 15 20 25 30 35 40 45 50
Minimum Elevation Angle (deg)
Effect of Antenna Rotation
G2
G1
Antenna
Fix G2
Rotation G1
0.0855
-0.0825
0.085
-0.083
Antenna Fix G1
Rotation G2
180°
Cannot find the offset
90°
-0.0835
180°
NS (m)
0.0845
NS (m)
G2
G1
90°
0°
0.084
270°
0.0835
270°
0°
-0.084
0.5mm
-0.0845
0.5mm
-0.085
0.083
0.0825
-0.898
-0.8975 -0.897
-0.8965 -0.896
EW (m)
-0.8955
-0.0855
0.895
-0.895
0.8955
0.896
0.8965
EW (m)
0.897
0.8975
0.898
Old Survey of SPring-8 Storage Ring
Using distance meter ME5000
Angle Measurement T3000
(1992~1993)
GPS survey
Receiver Net G3 (Topcon)
analysis software Pinacle
Specification
Static
Horizontal±（3mm+0.5ppm×Distance)
Vertical ±（5mm+0.5ppm×Distance)
13 degree
North
East
South
West
Shift for fifteen years
EW(mm) NS(mm)
SR1
7.3
-11.7
SR2
1.7
2.2
SR3
0.8
2.7
SR4
3.6
3.6
SR6
0.3
-2.9
SR7
-0.2
2.2
SR9
0.0
0.0
SR10
1.2
-0.8
Comparison GPS and ME5000
Comparison at 1000m distance
1050.6270
1050.6265
GPS (without correction)
Length(m)
1050.6260
1050.6255
1050.6250
1050.6245
1050.6240
2mm = 2 ppm
1050.6235
1050.6230
ME5000 =1050.6223 m(with air correction)
1050.6225
1050.6220
1
3
5
7
9
11
13
15
Time(hour)
17
19
21
23
25
1 0 0. 0 0 7
length
1mm
1 0 0. 0 0 5
1 0 0. 0 0 4
1 0 0. 0 0 3
1 0 0. 0 0 2
ME5000 100.0021m
100
80
Rain
3:00
19:00
11:00
19:00
humid_anzen
humid_68
humid_67
1.2
1
0.8
0.6
40
0.4
20
0.2
0
20
0
Rain (mm)
60
1/21 3:00
120
11:00
100
1/20 3:00
08/1/19 19:00
1 0 0. 0 0 1
Humidity (%)
length (m)
Effect of
Water Vapor
1 0 0. 0 0 6
Distance Comparison
200~400m
Distance GPS
(m)
(m) 1day
200
200.0052
ME5000
(m)
difference
(mm)
200.0049 0.3
300
300.0066
300.0060 0.6
400
400.0034
400.0028 0.6
Correction of water vapor pressure
Air Temperature：T[K]
Water vaper pressure：e [hPa]
He Ne laser λ= 633nm
0.073 * e
−6
n =1−
× 10
1 + 0.003661 * T
Micro wave
Water Vapor Pressure 0.2 hPa~ 1ppm
e
n = 1 + 3.73 × 2 × 10−3
T
Summary
Measured 8 Reference points by GNSS
only SR1 (on the filled ground) shift 14mm
Comparison ME5ooo and GPS
100m~400m distance difference ~1mm
Water vapor correction is very important.
Statistical error will be reduced using 20 Hz
Sampling.
I think we can reduce the precision of GPS using
high sampling rate and water vapor correction.