What does PDOP in RTK stand for...

Pdop (Position Dilution of Precision, which is a measure of X, Y, Z position geometry) position accuracy strength (0.5--99.9); it is the root value of the sum of the squares of errors such as latitude, longitude and elevation.

So the square of Pdop = the square of Hdop + the square of Vdop.

Specific meaning: Due to the geometric distribution of satellites, the better the distribution of satellites in the sky, the higher the positioning accuracy (the smaller the value, the higher the accuracy).

PDOP value: The spatial geometric intensity factor of satellite distribution. Generally, the better the satellite distribution is, the smaller the PDOP value is. Generally, less than 3 is an ideal state.

Introduction to RTK High-precision GPS measurement must use carrier phase observations. RTK positioning technology is a real-time dynamic positioning technology based on carrier phase observations. It can provide three-dimensional positioning results of the measuring point in the specified coordinate system in real time, and reaches centimeter level

Accuracy.

In RTK operation mode, the base station transmits its observation values ??and station coordinate information to the rover through the data link.

The rover not only receives data from the base station through the data link, but also collects GPS observation data, composes differential observation values ??in the system for real-time processing, and provides centimeter-level positioning results in less than one second.

The rover can be in a stationary state or in motion.

It can be initialized at a fixed point before entering dynamic operation, or it can be started directly under dynamic conditions and complete the search and solution of integer ambiguities in a dynamic environment.

After the solution of the entire week of unknowns is fixed, real-time processing of each epoch can be performed. As long as the tracking of the phase observations of more than four satellites and the necessary geometry can be maintained, the rover can provide centimeter-level positioning results at any time.