DGPS Report of Changunarayan and Laphipheidi
DGPS Report of Changunarayan and Laphipheidi
DGPS Report of Changunarayan and Laphipheidi
July, 2018
DGPS Survey of Lapsiphedi and Changunarayan Substation Construction Projects
1. Introduction ................................................................................................................ 1
7 Conclusion ................................................................................................................. 5
8 Annex: Photographs
List of Tables
Table 6.1: Coordinate of BASE
Table 6.2: Coordinates of Control Points in Project Area (WGS84)
Table 6.3: Transformation Parameters from Modified Everest1830 to WGS84
Table 6.4: Coordinates of Control Points in Project Area (Modified Everest 1830)
DGPS Survey of Lapsiphedi and Changunarayan Substation Construction Projects
1. Introduction
The DGPS survey of the control points has been carried on 22nd July 2018. This
report describes the adopted methodology for GPS data processing and the DGPS
results.
2. Work Description
Name Designation
Bikram Chokami Civil Engineer
Bidur Aacharya DGPS Surveyor
5. GPS Point Locations
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DGPS Survey of Lapsiphedi and Changunarayan Substation Construction Projects
Figure 5.2: Location of Lapsiphedi Substation site (gps points) in Project Area
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DGPS Survey of Lapsiphedi and Changunarayan Substation Construction Projects
The detailed approaches with data analysis and illustrations are given in subsequent
sections.
The precise coordinate of Base station point is determined by online precise point
positioning (PPP) services (AUSPOS and CSRS). The coordinate of the main base
station is computed based on more than 5 days observation data using L1/L2 bands.
With reference to above base station point, coordinate of the Changu trig station
point is determined and other coordinates are determined using GPS observation
with at least 40 minutes at all of 8 control points with reference to trig point using the
GNSS solution Software. The results of the processing are given below;
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DGPS Survey of Lapsiphedi and Changunarayan Substation Construction Projects
Table 6.2: Coordinates of Control Points in Project Area (WGS84 and UTM45N ZONE)
WGS84 Projected UTM 45N Zone
Station
S.N Ellips Ortho
Name Longitude latitude East North
height height
1 Gps1 85° 25' 54.19919"E 27° 43' 33.33166"N 1288.919 345403.547 3067826.843 1335.356
2 Gps2 85° 25' 53.59096"E 27° 43' 35.32736"N 1288.973 345387.672 3067888.476 1335.395
3 Gps3 85° 25' 50.13996"E 27° 43' 24.77637"N 1303.628 345289.023 3067564.960 1350.145
4 Gps4 85° 25' 46.74875"E 27° 43' 21.28676"N 1320.185 345194.778 3067458.747 1366.738
5 Gps5 85° 30' 13.98158"E 27° 44' 39.15740"N 1615.594 352542.623 3069764.139 1661.080
6 Gps6 85° 30' 17.15061"E 27° 44' 38.35594"N 1603.965 352629.095 3069738.419 1649.454
7 Gps7 85° 30' 19.89936"E 27° 44' 40.46307"N 1604.511 352705.147 3069802.353 1649.981
8 Gps8 85° 30' 35.04141"E 27° 44' 51.07722"N 1562.716 353123.712 3070123.982 1608.091
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DGPS Survey of Lapsiphedi and Changunarayan Substation Construction Projects
7 Conclusion
The coordinate of the main base station (KTM1) is computed based on more than 5
days observation data using L1/L2 bands by online precise point positioning (PPP)
services (AUSPOS and CSRS). Coordinates of other ground control points are
computed with reference to Base station point using GNSS solution software by
Trimble Navigation Limited. A total 8 control points has been established in the
project area.
The control points coordinates are also transformed to Nepalese Coordinate System
Modified Everest84 (Nagarkot Datum) from WGS 84 using the three parameters
transformation. These control points are precise to centimeter and can be used for all
project works.
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DGPS Survey of Lapsiphedi and Changunarayan Substation Construction Projects
DGPS Survey of Lapsiphedi and Changunarayan Substation Construction Projects
Gps1 Gps2
Gps3 Gps4
DGPS Survey of Lapsiphedi and Changunarayan Substation Construction Projects
Gps5 Gps6
Gps7 Gps8