[Everyone can use RTK] Satellite based positioning relies on measuring distance between satellite and receiver. There are two types of positioning mode, one is point position and the other is relative position. Real time kinematic (RTK) positioning is a kind of relative position. Relative positioning cancels most error sources in distance measurement by making difference between two receivers, so it is more simple and reliable. RTK can be used in challenging environments where there is high interference, multipath effects and occlusions. For surveying or GIS-related applications, the traditional requirement for positioning accuracy was at meter or sub-meter level, in static mode. However, emerging applications such as UAV surveying & mapping not only require high precision at centimeter level, but also operate in moving, kinematic modes. RTK is not yet deployed in surveying and mapping on a large scale. The cost is still high. The rapid development is bringing RTK tech