Briefly describe RTK high-precision positioning technology

2024-08-27/ By Admin

1、 What affects the positioning accuracy? Why do different modules have different positioning accuracies?

The GNSS module we usually use, also known as a satellite signal receiver, receives observations sent by satellites, which are subject to ionospheric, tropospheric, and ground interference. The accumulation of errors leads to a significant decrease in positioning accuracy.

According to the different frequency bands received by the receiver, GNSS modules can be divided into single frequency and dual frequency. Single frequency GNSS modules only receive single frequency signals from satellites, while dual frequency GNSS modules can receive signals from two frequency bands sent by satellites. Dual frequency can effectively eliminate relative errors, and the positioning accuracy is much higher than that of single frequency.

According to the different ways in which GNSS modules process observations, they can be divided into single point positioning (absolute positioning) and differential positioning. The positioning information output by single point positioning (absolute positioning) only calculates the received observations from four satellites; Differential positioning, on the basis of calculating observations from four satellites, reduces errors and outputs more accurate positioning results by receiving correction information sent by observation stations.

2、 RTK Overview

RTK (Real time kinematic), also known as carrier phase difference technology, can provide real-time three-dimensional coordinates of two measurement stations by processing the carrier phase observations in real-time, achieving centimeter or millimeter level high accuracy.

Network RTK: A positioning method that establishes multiple (usually three or more) reference stations within a certain area, forms a network coverage of the area, and uses these multiple reference stations as benchmarks to calculate and continuously broadcast various error and phase difference correction information, and performs real-time correction for centimeter level precision satellite positioning users in the area. It is also known as multi reference station RTK.

3、 About the high-precision RTK module produced by Shenzhen Tiangong Measurement and Control Co., Ltd

Module: SKG123NR/SKG122ER/SKG122GR

GMouse: SKM3507MR, etc