Network RTK Technology And Foundation Control Construction Method Study

At present GPS RTK technology is widespread on using surveying technology, after being published of this technology, has expanded the GPS extensive field, enables GPS only to get rid from the control domain, so it is widely utilized in each kind of survey domain.But it's come influence under broadcasting station's transmission mode, along with the distance's increase of reference station and moving station, the signal weakened, increased the time delay, this has limited the operating region of traditional RTK. According to this flaw to establishes the multi-datum station network RTK system to eliminate the traditional RTK technology the insufficiency, but establishes the Multi-reference station network RTK system's construction expense and the maintenance expense are big, without the superiority in northern area of the ionosphere weak, so it requested us to find one new method to overcome these flaws, then people proposed the single reference station network RTK technology.This paper through to traditional RTK and the Multi-reference station network RTK analysis, as well as the ionospheric disturbance quite small characteristic of northern area, the research established the GPS RTK system that suit the northern area. Because the present survey work needs a millimeter level, the centimeter level data, and needs decimeter level data which conform to the GIS request, so proposed that establishes the multi-purpose GPS difference system, this method through the establishment foundation control net to solve coordinate transformation parameter, uses the network communication to replace broadcasting station's data transmission way and transmit carrier wave difference signal and the code difference signal. This method's principal advantage is the funding invested are few, momentarily may promote and expand, nimble reliable stable, does not need to report the flowing stand position the bidirectional data transmission set, the construction cycle short and so on merits.Through the theoretical analysis and present demand, the multi-purpose GPS difference system which establishes in Anshan Tai'an County, achieves the centimeter level after the examination precision. Therefore, obtains regarding our country northern area, the urban radius can not surpass 40km, applies the multi-purpose GPS difference system not only to be possible to satisfy each kind of routine measurement, moreover can also complete a decimeter level the data of GIS, achieves the requirements of the urban survey, has the strong utility. May simultaneously realize for the survey, the earthquake, the meteorology, the land resources, the transportation, the water conservation, the minerals, the forestry, the agriculture, the environmental protection and so on many professions can carry the data acquisition service of many kinds of spatial data pools.