RTK GPS & GPS SURVEY
Introduction of GPS Survey & RTK GPS


Introduction of GPS Survey & RTK GPS
Many private engineering practices require significant investment. Therefore, an accurate cost estimate is fundamental for the success of any project. The topography is basic to many earth surfaces and thus topical surveying is one of the applications used to obtain necessary and pertinent data. Inaccurate survey results in a topographic map that does not represent the construction area will make a biased or erroneous investment.
Since survey-based private companies work in a competitive business environment, there is a need to demonstrate that they are above others in terms quality and that their strategic direction is more realistic and focus than perhaps government entities: they must provide expedient as well as accurate methodologies to gain their client’s confidence. Therefore, they always implement the newest, most precise, and most efficient methods in line with their financial capabilities.
Over the past decade Real Time Kinematic, RTK surveying with Global Navigation Satellite Systems (GNSS) has become common practice in geomatics. RTK surveying is a relative positioning technique that measures positions using two GNSS antennas in real-time. One is set up on a static point with fixed coordinates and is known as the base station. It uses a high-frequency radio to transmit its raw observations to the second unit (known as the rover) and then the rover uses both observations to compute a position relative to the base location in real-time. RTK surveying requires reliable communication between base and rover units and works best with short baselines as the precision of RTK measurements decreases as the baseline length increases.
Evaluation of GPS-RTK and Total Station for Topographic Survey and Strategic Decision in Private Companies
Abstract
An accurate and efficient survey system is needed for survey-based private companies to survive in the business and engineering world. Accuracies of GPS-RTK (Global Positioning System-Real Time Kinematic) system and TS (Total Station) were investigated in a topographic survey. The hypothesis proposed was that the GPS-RTK system could be an alternative survey for moderate accuracy projects. 5.90 ha salt ponds area became a sample for the research. A full detailed measurement was conducted by both instruments to build a contour map. Time expenditure was recorded to identify each method of effectiveness. The maximum offset of elevation was 0.054 m (polygon) and 0.098 m (detail). The survey results demonstrated that even though the GPS-RTK system was not only practical and efficient (time-saving reached 30% versus TS and 33% more efficient in human resources) but also yielded acceptable accurate topographic maps for moderate accuracy engineering purposes, the GPS-RTK system cannot be conducted for every terrain feature.
Keyboards
GPS-talk system, Total Station, Topographic Survey, Project Assurance, Cost Control.
The GPS-RTK (Global Positioning System – Real-Time Kinematic) system is considered. The most useful system for topographic surveys between satellite survey technologies. Utilization of this system for surveys of multi-functional networks and, sometimes, also the detailed 3rd order network, is becoming more popular. The factor which makes surveys using the RTK measuring set more difficult within specific areas is the presence of terrain obstacles. These can limit the simultaneous communication of the basic receiver and the mobile receiver as well as interfere with the necessary communication among the five satellites required for GPS to be 100% reliable. GPS-RTK based surveys are not only practical and fast but also yield more accurate topographic maps for design purposes (for an open area with no obstacles and using a model to generate contours).
In many construction and estate monitoring processes, observations are obtained by TS (Total Station). Furthermore, it is stated that TS is a more suitable method to conduct topographic surveying than using a Theodolite for private companies within Indonesia, whether this is undertaken by the owner, contractor, or consultant.
Not only does this instrument provide good accuracy, but also provides automatic computation for the data. Total Station observation achieves only a 1 mm standard deviation. The focus of this research is to evaluate the accuracies of the RTK survey by Geodetic GPS and Tachometric survey by TS in land surveying for construction practices, both for medium (cm class) and high (mm class) accuracy projects (this test was for land trade’s practice).
This goal was achieved through the following specific objectives:
1. Evaluating the result and accuracy obtained from GPS-RTK and TS.
2. Using supervised classification to perform data analysis provided from each data source.
3. Comparing the contour map provided from each data source; and
4. Evaluating the cost (time expenditure) of both systems.
GPS SURVEY
What is GPS?
The full meaning of GPS is the Global Positioning System. The location of road ghats in any area can be known using the internet, With GPS we can know the latitude, longitude, altitude, time of a place and create different types of maps. The one who can best identify the country’s borderline is called GPS.
How is GPS Used in Surveying?
Surveying and mapping were one of the first commercial adaptations of GPS, as it provides a latitude and longitude position directly without the need to measure angles and distances between points. However, it hasn’t entirely replaced surveying field instruments such as the theodolite, Electronic Distance Meter, or the more modern Total Station, due to the cost of the technology and the need for GPS to be able to ‘see’ the satellites, therefore, restricting its use near trees and tall buildings. In practice, GPS technology is often incorporated into a Total Station to produce complete survey data. GPS receivers used for baseline measurements are generally more complex and expensive than those in common use, requiring a high-quality antenna. There are three methods of GPS measurement that are utilized by surveyors.
- Static GPS Baseline. Static GPS is used for determining accurate coordinates for survey points by simultaneously recording GPS observations over a known and unknown survey point for at least 20 minutes. The data is then processed in the office to provide coordinates with an accuracy of better than 5mm depending on the duration of the observations and satellite availability at the time of the measurements.
- Real-Time Kinematic (RTK) Observations. This is where one receiver remains in one position over a known point – the Base Station – and another receiver moves between positions – the Rover Station. The position of the Rover can be computed and stored within a few seconds, using a radio link to provide a coordinate correction. This method gives similar accuracy to baseline measurements within 10km of the base station.
- Continuously Operating Reference Stations (CORS). This where a survey quality GPS receiver is permanently installed in a location as a starting point for any GPS measurements in the district. Common users of CORS are mining sites, major engineering projects, and local governments. Surveyors’ GPS receivers can then collect field data and combine it with the CORS data to calculate positions. Many countries have a CORS network that is used by many industries. Australia’s CORS network is the Australian Regional GPS Network, and uses an online processing system to deliver data over the internet within 24 hours, and give positions within an accuracy of a few centimeters. Local CORS networks are also used to provide instant positions similar to the RTK method by using a mobile phone data link to provide a coordinate correction to the surveyor and their rover.
Service Description
We provide a broad range of GPS & DGPS Survey Services:In GPS & DGPS Survey using latest GPS & DGPS for Roads, Highways, Pipeline, canal route studies, Site plan preparations, Hydrographic Surveys, Reservoir studies, River studies, Inundation mapping studies, Traverse adjustment with network etc.Our dedicated teams of professionals work closely with our client and offer personalized and cost effective solutions.
DGPS Survey Services, Soft And Hard Copy, Client Side
By understanding the demands of our patrons in the best possible way, we are increasingly engrossed in offering DGPS Survey Services to our clients. Delivered in tune with the standards defined by the industry, these services are enormously in demand. Due to their cost-effectiveness, these provided services are hugely treasured.
With the support of talented professionals, we are involved in providing highly effective GPS Survey to our prestigious clients. The provided services are rendered in different fields with the best client satisfaction and requirements. Also, this GPS survey service is available to us in many types at pocket-friendly rates.
Get Latest Price
A Differential Global Positioning System (DGPS) is an enhancement to the Global Positioning System (GPS) which provides improved location accuracy, in the range of operations of each system, from the 15-meter nominal GPS accuracy to about 1-3 cm [1] in case of the best implementations. Each DGPS uses a network of fixed.