Testing Survey Grade GNSS Systems on the Curtin Test Network
1. Introduction
These guidelines apply only in Western Australia and are issued under the direction of the
Surveyor General. They describe a suggested practice for testing Global Navigation
Satellite System (GNSS) - hardware, firmware and software for surveying applications on
the test network at Curtin University. The aim of the guidelines is to encourage all surveyors
to employ a uniform approach when testing their equipment so the results obtained provide
a reliable validation of user systems. Some requirements for testing on the network may not
reflect the surveyor’s normal operational usage of that system, particularly with respect to
data collection rates and the number of satellites observed.
It is emphasised that these guidelines do not represent legal traceability of measurement
and position by GNSS.
These guidelines are specific to using GNSS in circumstances that follow a quality
assurance approach. The following understandings and limitations therefore apply:
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These guidelines apply to GNSS hardware and software systems designed for
geodetic survey applications operated in differential mode where carrier phase and
pseudo-range observations are recorded by the receivers.
All equipment used in the test will be in good working order and adjustment and the
GNSS antennae will be oriented correctly throughout the test.
Because approved methodologies for establishing legal traceability of length
measurement for GNSS do not currently exist under the Australian National
Measurement Act (1960), GNSS should not be used as the sole method of
measuring length in legal surveys. Surveyors using GNSS for legal purposes must
adhere to the requirements of the Surveyor General as the appropriate verifying
authority and Chairman of the Land Surveyors Licensing Board in this State.
2. Frequency of testing
Surveyors should test their GNSS systems on the network at Curtin at least once per year,
immediately after any repair, after a system upgrade (hardware and/or firmware) and after
any upgrade of the post-processing software. Surveyors using multiple post processing
software packages for their GNSS operations should compute the GNSS baseline
observational data with all programs.
3. Minimum requirements for testing GNSS
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The Geocentric Datum of Australia 1994 coordinates (GDA94) promulgated by
LANDGATE will be used to perform all processing.
Receivers will be set to record at a 5 second data collection rate.
The minimum constellation specification to be simultaneously observed by all
receivers is: 5 common healthy satellites having an elevation angle of 150 or more
above the horizon and a GDOP of 8 or less.
Enough data must be observed to produce an Ambiguity Fixed baseline solution
and/or a Standard Deviation of less than 3 mm.
A braced quadrilateral formed by APPLECROSS 97 (PILLAR 20), PILLAR 16,
PILLAR 18 and PILLAR 19 shall be observed. The six baselines are to be observed
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Updated 27/01/2012
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and processed as independent vectors. Please note that due to tree cover, PILLAR
17 is now unsuitable for GNSS occupation. PILLAR 15 can be included in the
network but due to tree cover has a restricted western view to the sky.
Users should follow the recommendations set out in the manufacturer's handbook
and manuals. All ancillary equipment must be in good adjustment and repair.
Field observation recording sheets similar to the type in Appendix A should be
completed for each session. The receiver type, serial number and firmware used
must be recorded on these sheets.
Meteorological readings are optionally recorded but should not be used in the GNSS
processing. The reduction software defaults for tropospheric modelling are to be
used.
A minimally constrained least squares adjustment of the observed baseline network
must be carried out holding APPLECROSS 97 (PILLAR 20) fixed at the official
LANDGATE values, to verify that the survey meets the required standards. All
adjustments of GNSS data should be 3 dimensional in terms of the Geocentric
Datum of Australia.
Post adjustment base line vectors (chord distances - Pillar to Pillar) should then be
compared with the promulgated LANDGATE values. Acceptance criteria are given as
5 millimetres or better. Other checks may be specified for surveyors engaged on
government contracts requiring a particular CLASS of survey.
4. Data retention
Surveyors are encouraged to suitably archive raw observational data, adjustment results
and baselines.
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Updated 27/01/2012
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5. Curtin University GNSS Test Network Coordinates
5.1 Station Information
Station
GDA94
PILLAR 15*
Station
GDA94
PILLAR 16
Cartesian
Latitude:
S 32 00 04.32714
X:
-2 363 824.111
Longitude:
E 115 53 17.35392
Y:
4 870 666.246
Ellipsoidal Height:
-22.597
Z:
-3 360 532.490
Orthometric Height (AHD):
9.528
MGA94
PCG94
Easting
394978.648
Easting
56754.956
Northing
6458891.034
Northing
258015.378
*PILLAR 15 can be included in the network but due to tree cover has a restricted western view
to the sky.
Cartesian
Latitude:
Longitude:
Ellipsoidal Height:
Orthometric Height (AHD):
MGA94
Easting
Northing
Station
GDA94
S 32 00 12.82263
E 115 53 30.23811
-20.778
11.327
X:
Y:
Z:
-2 364 068.467
4 870 395.214
-3 360 755.362
Easting
Northing
57092.956
257753.472
PCG94
395319.404
6458632.911
PILLAR 17**
Cartesian
Latitude:
S 32 00 17.30041
X:
Longitude:
E 115 53 23.57802
Y:
Ellipsoidal Height:
-21.164
Z:
Orthometric Height (AHD):
10.950
MGA94
PCG94
Easting
395146.068
Easting
Northing
6458493.238
Northing
**PILLAR 17 is now unsuitable for GNSS occupation due to tree cover.
Station
PILLAR 18
GDA94
Latitude:
Longitude:
Ellipsoidal Height:
Orthometric Height (AHD):
MGA94
Easting
Northing
S 32 00 21.54205
E 115 53 24.45849
-21.987
10.125
395170.511
6458362.866
-2 363 879.145
4 870 405.489
-3 360 872.118
56918.054
257615.668
Cartesian
X:
Y:
Z:
-2 363 869.395
4 870 332.476
-3 360 982.473
PCG94
Easting
Northing
56941.075
257485.001
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Updated 27/01/2012
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5.1 Station Information Continued
Station
GDA94
PILLAR 19
Cartesian
Latitude:
Longitude:
Ellipsoidal Height:
Orthometric Height (AHD):
MGA94
Easting
Northing
Station
GDA94
S 32 00 02.40847
E 115 53 26.15702
-22.281
9.837
X:
Y:
Z:
-2364045.775
4870593.773
-3360482.539
Easting
Northing
56986.058
258074.321
X:
Y:
Z:
-2 363 821.788
4 870 529.874
-3 360 734.112
Easting
Northing
56812.253
257778.802
PCG94
395209.030
6458952.487
PILLAR 20 (Applecross 97)
Cartesian
Latitude:
Longitude:
Ellipsoidal Height:
Orthometric Height (AHD):
MGA94
Easting
Northing
S 32 00 12.00646
E 115 53 19.54284
-20.649
11.476
PCG94
395038.515
6458655.162
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Updated 27/01/2012
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5.2 Station Difference Information
From Station
Pillar 20 (Applecross 97)
Azimuth Forward
Chord Distance
From Station
Pillar 20 (Applecross 97)
Azimuth Forward
Chord Distance
From Station
Pillar 20 (Applecross 97)
Azimuth Forward
Chord Distance
From Station
PILLAR 16
Azimuth Forward
Chord Distance
From Station
PILLAR 16
Azimuth Forward
Chord Distance
From Station
PILLAR 18
Azimuth Forward
Chord Distance
From Station
PILLAR 16
Azimuth Forward
Chord Distance
From Station
PILLAR 16
Azimuth Forward
Chord Distance
From Station
PILLAR 18
Azimuth Forward
Chord Distance
95 07 05.53
281.842
To Station
PILLAR 16
Azimuth Reverse
Spheroidal Distance
275 06 59.86
281.843
156 17 09.31
320.804
To Station
PILLAR 18
Azimuth Reverse
Spheroidal Distance
336 17 06.71
320.803
30 25 23.24
342.844
To Station
PILLAR 19
Azimuth Reverse
Spheroidal Distance
210 25 19.74
342.841
209 27 29.37
308.456
To Station
PILLAR 18
Azimuth Reverse
Spheroidal Distance
29 27 32.44
308.454
341 32 01.39
338.191
To Station
PILLAR 19
Azimuth Reverse
Spheroidal Distance
161 32 03.55
338.189
4 19 33.74
591.033
To Station
PILLAR 19
Azimuth Reverse
Spheroidal Distance
184 19 32.84
591.035
307 43 52.86
427.599
To Station
PILLAR 15
Azimuth Reverse
Spheroidal Distance
127 43 59.69
427.596
231 43 32.69
222.666
To Station
PILLAR 17
Azimuth Reverse
Spheroidal Distance
51 43 36.22
222.667
340 37 27.10
562.084
To Station
PILLAR 15
Azimuth Reverse
Spheroidal Distance
160 37 30.87
562.085
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Updated 27/01/2012
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5.2 Station Difference Information Continued
From Station
PILLAR 18
Azimuth Forward
Chord Distance
From Station
PILLAR 19
Azimuth Forward
Chord Distance
From Station
PILLAR 19
Azimuth Forward
Chord Distance
From Station
PILLAR 15
Azimuth Forward
Chord Distance
349 58 09.42
132.681
To Station
PILLAR 17
Azimuth Reverse
Spheroidal Distance
169 58 09.89
132.679
255 39 08.68
238.500
To Station
PILLAR 15
Azimuth Reverse
Spheroidal Distance
75 39 13.35
238.500
188 23 40.34
463.668
To Station
PILLAR 17
Azimuth Reverse
Spheroidal Distance
8 23 41.71
463.668
157 45 52.92
431.706
To Station
PILLAR 17
Azimuth Reverse
Spheroidal Distance
337 45 49.62
431.705
Notes
1. Station and Station Difference Information is in GDA94
2. Chord distance = Pillar to Pillar measured and legally traceable slope chord distance at stainless steel
plate.
3. Heights are at stainless steel plate
4. Orthometric heights are Australian Height Datum (AHD)
5. Ellipsoidal Heights are an observed value and not derived using AUSGEOID98.
6. Projected coordinates are MGA94 Zone 50 and Perth Coastal Grid 1994 (PCG94)
7. PILLAR 15 can be included in the network but due to tree cover has a restricted western view to the
sky. PILLAR 17 is now unsuitable for GNSS occupation due to tree cover.
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Updated 27/01/2012
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Appendix A - Station Log Sheet:
Curtin GNSS Test Network
Occupied Pillar Number
Receiver Operator
Company/Agency Owning Equipment
Receiver
Type
Model
S/No
Antenna
Type
Model
S/No
Receiver Firmware Type & Version
NB Data Collection Rate is to be set to 5 seconds
Observation Times (WA Std Time)
Today's Date
Start Time
End Time
Session Number
Temperature
Pressure
Relative Humidity
Observing to Pillar Number(s), this Session
The Antenna MUST be Oriented to North. Antenna height above mark in metres enter the vertical height to the antenna reference point.(ARP)
Height of ARP
Record the measured height above the Pillar Plate, for as many of the following
points on the antenna as possible.
Distance (metres) vertical slant Offset Distance
L1 Phase centre
L2 Phase centre
Base of antenna
Top of ground plane
Bottom of ground plane
Bottom of choke ring
Certification: This is a true and correct record of the observations taken and
recorded by me or under my supervision at the GNSS Test Network situated
at Curtin University.
Signed
Print Name
Date
NB: Retain this form as part of the Test Record
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Updated 27/01/2012
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