Please help me to explain the meaning of single point solution, floating point solution, fixed solution and difference decomposition in GPS, and it is best to give examples.

Single-point solution: When RTK is working, the mobile station and the reference station cannot be contacted, only the mobile station is working, and generally there is no data display.

Floating point solution: the accuracy is relatively high, and sometimes it can barely reach the accuracy within 10CM. This accuracy can also be used if measuring fish ponds or mountains.

Fixed solution: It is the most accurate data with an accuracy of 3-5CM, which can basically be used as the root point of drawings or directly used for lofting.

Difference decomposition: There is a signal, but due to various reasons, such as too few satellites or poor location of mobile stations, the accuracy of rendezvous data is very low, with a general deviation of several meters or more than ten or twenty meters.

For example:

Fixed solution: its positioning accuracy is within 1cm, which can meet the needs of high-precision surveying and mapping work such as topographic surveying and mapping, construction lofting and root point measurement at various scales except the first-level control survey.

Floating point solution: If the positioning accuracy of floating point solution is less than 0.5m, the plane and elevation error is generally 0. 1-0.3m according to experience, which can meet the surveying and mapping work with the accuracy requirement not exceeding 0.5m; If the positioning accuracy is greater than 0.5m, the plane and elevation errors are generally 1-3m.

The positioning accuracy of differential decomposition and single-point solution is generally between 5- 10 meter, and sometimes it is larger, so it is generally not used.

Extended data:

GPS system is mainly composed of space constellation, ground monitoring and user equipment.

The GPS constellation consists of 24 satellites, of which 2 1 are working satellites and 3 are backup satellites. These 24 satellites are evenly distributed on six orbital planes, that is, there are four satellites on each orbital plane.

The orbital inclination of the satellite orbital planes is 55 relative to the equatorial plane of the earth, and the right ascension of the ascending intersection of each orbital plane is 60. The ascending angle distance of the satellite on one orbital plane is 30 ahead of the corresponding satellite on the adjacent orbital plane in the west. The purpose of this layout is to ensure that at least four satellites can be observed anywhere in the world at any time.

The ground monitoring part is mainly composed of 1 master station, 4 ground antenna stations and 6 monitoring stations.

The global positioning system of the master station is the management center and technical center of the whole ground monitoring system.

At present, there are four injection stations, which are used to inject satellite ephemeris, navigation messages and other information calculated by the main control station into the corresponding satellites.

The injection station is also a monitoring station. The main function of the monitoring station is to collect GPS satellite data and local environmental data, and then send them to the main control station.

The user equipment is mainly a GPS receiver, and its main function is to receive signals from GPS satellites and calculate the user's three-dimensional position and time by using the transmitted information.

References:

Baidu encyclopedia -—GPS