GNSS application in Nepal
- 1. GNSS Presented By: Ashok Kumar Rimal
- 4. 1 NEPAL • landlocked country located between India to the east, south, and west and the Tibet Autonomous Region of China to the north 3 Introduction • Total area: 147,516 km² • Nepal lies between 80.4' and 88.12' east longitude and 26.22' and 30.27' north latitude • Standard time: GMT+05:45 all over Nepal
- 6. 1 Introduction GNSS • include constellations of Earth-orbiting satellites that broadcast their locations in space and time, of networks of ground control stations, and of receivers that calculate ground positions by trilateration • GPS, GLONASS, GALILEO, COMPASS, IRNSS, QZSS 5
- 7. 2 • In 1970, establishment of Trigonometrical Survey branch under survey department • In 1976, establishment of Geodetic Survey branch • Control network was defined through the use of conventional measurements. i.e. Precise Leveling, Astronomical and Gravity Observations • Geodetic Survey Division commenced the use of GPS technology in 1991 A.D for carrying out land survey. • initiated the use of GPS for survey of previously established high order control points • Everest to WGS-84 • Need Transformation parameters 6 History
- 8. 2 • Establishment of different (first/second/third) for strengthening the geodetic network • GNSS observation are done regularly as yearly development program • Develop semi dynamic datum for the country • Determination of ground displacement of 25 April 2015 Nepal earthquake by GNSS precise point positioning • Used GNSS for setting up GCP points for RS image rectification • CORS setup: first in Nagarkot observatory • Height determination process of the Mt. Everest 7 History
- 10. 3 Application: Status 9 Geodetic Survey Division • Geodetic Survey Division maintain/operate 2 CORS station at Nagarkot. • Establishment of CORS station at front field of Survey Department office at Minbhawan, Kathmandu. The construction is going on. • Geodetic Survey Division is planning to establish more than 50 CORS station covering whole country. The work of initial phase is on the floor. • Resurvey of past control points (First order/second order) by GNSS method. • Establishment of network of control points required for re-cadastral survey such as in Siraha, Saptari district by GNSS method. • GPS observations of the geodetic stations for regional/local transformation parameter (WGS 84 to Everest 1830 and vice-versa.) • GNSS survey at level benchmarks along the level alignment. • The positioning of Airborne Gravity 2010 was from onboard GNSS sensor and ground reference GNSS control stations.
- 11. 3 Application: Status 10 Topographical Survey and Land Use Management • GNSS survey to assist in surveying & delineating international boundaries of the country with neighboring countries. (Border survey/India-Nepal border/China- Nepal border) • GCP establishment by GNSS method to prepare & update the topographical base maps of the country. (topo map update using ZY3 satellite image provided by china/such satellite image georeferenced with GCP established by GNSS method) • Survey Department is conducting LIDAR survey of Terai region extending from CHITAWAN -TO- KANCHANPUR. The positioning of LIDAR point clouds will come from GNSS method
- 12. 3 Application: Status 11 UNAVCO and DMG: • CORS stations are established by UNAVCO and Department of Mines and Geology in Nepal. There are 11 existing 11 CORS network stations and 5 new CORS stations. • 11 existing CORS stations: JMLA, NPGJ, JMSM, BESI, CHLM, NAST, SYBC, SNDL, RMJT, BRNZ. • 5 new CORS stations: DLPA, DNSG, HETA, CHWN, KLCK.
- 13. 3 Application: Status 12Fig. Epicenter (star) and GNSS station (triangle) displacement vectors Displacement Determination of 25 April 2015 Earthquake
- 14. 3 Application: Status • collected and processed GNSS data at 17 stations around the epicenter • GNSS station displacements are calculated precisely with an accuracy of 1cm in the horizontal and the vertical components • show that the affected area stretches about 160 km in the south-eas • common moving direction is close to the south-southeast with the maximum value of 2 m in the horizontal component 13 Displacement Determination of 25 April 2015 Nepal Earthquake Figure. Displacements of stations KKN4 (left) and NAST (right), accepted from (Galetzka J., 2015)
- 15. 3 14 Because of the effect of plate tectonic motion, the actual position of points on the earth changes continuously. However nearly all users find it difficult to deal with continuous coordinate change. Modern semi-dynamic datum are based on a version of the International Terrestrial Reference Frame. Stable coordinates are produced by projecting each coordinate to its position at a common date called the reference epoch. In this case a mathematical model, usually a National Deformation Model, is used to calculate the trajectory of points. The effect of earthquake is an instantaneous offset while the effect of the velocity increases linearly with time. The total motion is just the sum of the earthquake and the constant velocity terms. Application: Status Semi-Dynamic Datum
- 16. 3 15 Figure 5: Basic NDM model where trajectory of points effected by a constant velocity and two earthquakes Application: Status Semi-Dynamic Datum
- 17. 3 16Figure 5: Air-Route chart of National and International flights Application: Status PBN Implementation Plan
- 18. 3 17 • At the 36th Session of ICAO Assembly, it has been resolved: “All the contracting States should have a PBN implementation plan in place by 2009 to ensure a globally harmonized and coordinated transition to PBN by 2016” • The objective is to provide the continuity to the development in the field of air navigation including the GNSS-based procedures- a step for transitioning to PBN • CAA Nepal completed WGS-84 survey of the runway thresholds, critical positions of runway and Navigation Aids of TIA and all domestic airports in operation in 1999 and data have been published in the AIP Nepal • Re-verification of WGS-84 data and survey of other essential points at Kathmandu & Biratnagar Airports has been carried out in 2010 • To take early benefit of the satellite based navigation, GNSS based approach procedures for TIA and 8 major domestic aerodromes were developed in 1999, some of them were flight validated • GNSS NPA procedures were reviewed and some GNSS/RNAV departure procedures were developed based on PANS/OPS in 2005. Some of them were flight validated. • GNSS based approach and departure procedures have been designed at about nine domestic airports including Tribhuvan International Airport and some of them have been flight validated Application: Status PBN Implementation Plan
- 19. 3 18 • Used satellite image as a primary data • Needed of geo-referencing • Select the required nos of GCPs and taking the coordinates of that points by using GNSS receiver Application: Status National Land Use Project
- 20. 3 19 • Over 8,000 boundary pillars along the Indo-Nepal border will be equipped with positioning system using Global Navigation Satellite System • Nepal-India Boundary Global Navigation Satellite System (NIB GNSS) would be used for Nepal-India boundary pillars Application: Status Boarder Measurements
- 21. 3 20 • GNSS based survey was conducted for determining locations of gravity points, bench marks as well as top of Mt. Everest • GNSS survey was conducted for 1 hour 16 minutes on the top of the world Application: Status Mt. Everest Height Measurements
- 22. 3 21 Application: Status Location Based Services
- 23. 3 22 Application: Status Disaster Risk Reduction Management (DRRM) Many peoples (> 55%) in Nepal reside in areas that are vulnerable to natural disasters.
- 24. 23 4 Conclusion GNSS systems where revolutionary in the area of Navigation by providing positioning and navigation capabilities to the autonomous vehicles. With precise positioning, GNSS can be used for lane or track determination (for road and rail vehicles) and attitude determination by using multiple antennas Nepal has applied the GNSS systems in many dynamic fields. i.e. Surveying and Mapping, DRM, LBS, Planning, Weather Forecast, Future Risk Prediction etc. There are many furthermore application of GNSS which are already used other country but Nepal still has not Needed of upgrading the technology, producing the skilled manpower, increasing the budget for GNSS application
- 25. 24 5 REFERENCES • https://www.nepjol.info/index.php/NJG/article/view/23009 • https://www.unoosa.org/documents/pdf/psa/activities/2014/trieste- gnss/43.pdf • https://mycoordinates.org/united-nationsnepal-workshop-on-the-applications- of-gnss/ • https://www.gisresources.com/india-nepal-border-pillars-to-be-gps-enabled/ • https://www.geospatialworld.net/article/application-of-remote-sensing-and- geographical-information-system-gis-in-forest-survey-in-nepal/ • https://www.researchgate.net/publication/315499261_Measuring_ground_defo rmations_caused_by_2015_M_w78_Nepal_earthquake_using_high- rate_GPS_data_and_its_application_to_seismology • https://www.researchgate.net/publication/332350732_Opportunities_and_Chall enges_of_Geospatial_GeomaticsSurveying_Education_in_Nepal • https://mycoordinates.org/towards-a-modernized-geodetic-datum-for-nepal/
Editor's Notes
- #4: Nepal is one of the beautiful country of world. It is known by the country of Himalayan, -the country of mount Everest -The country where lord Buddha was born -the world’s brave soldiers, the Gorkha -the city of temple
- #17: Because of the effect of the 25th April, 2015 Gorkha earthquake, significant earth deformation has occurred in a large area of Nepal centered on the Kathmandu Valley. As a result, the geodetic control in this region is significantly distorted with published geodetic control coordinates being displaced from their true position on the ground by up to 2m. Correcting these distortions will require a new geodetic datum. The possibility of Nepal adopting a semidynamic datum, which would be based on ITRF2014 and include a national deformation model capable of correcting for the recent earthquakes and normal tectonic motion. We demonstrate that it is possible to develop a deformation model for Nepal incorporating the Gorkha earthquake and the variation of the long term (or secular) crustal velocity across the country using published information. While this model is preliminary our test shows that its use does a good job of correcting survey measurements for the effect of the earthquake.
- #23: The riding apps Pathao, Tootle, Taximandu etc uses the Google maps for navigation the location of passengers. Similarly online shopping apps i.e NPL Market, Daraz, and many others are uses the GNSS signals for finding customers. Same as riding apps and online shoping, the food delivery apps Foodmandu serves theirs customers as follow the direction shown by Google maps. Others many location based services are depended on GNSS systems.