Coordinate conversion method and system

Abstract

The invention discloses a coordinate conversion method and system, and the method comprises the steps: selecting two reference points, and respectively obtaining the coordinates of the two reference points in a rectangular coordinate system and a longitude and latitude coordinate system; calculating the distance between the two datum points under the rectangular coordinate system and the longitudeand latitude coordinate system, when the difference value of the two distances is smaller than or equal to a preset threshold value, constructing a tangent plane of the earth at one datum point and constructing a middle rectangular coordinate system on the tangent plane, and taking the longitude and latitude coordinate of the datum point as an original point of the middle rectangular coordinate system; the longitude and latitude lines of the datum point being respectively a Y axis and an X axis; establishing a conversion relationship between a longitude and latitude coordinate system and an intermediate rectangular coordinate system; calculating the coordinate of the other reference point in the middle rectangular coordinate system, and calculating a conversion matrix between the rectangular coordinate system and the middle rectangular coordinate system; and converting the coordinates between the longitude and latitude coordinate system and the rectangular coordinate system accordingto the conversion relationship and the conversion matrix.

Description

technical field [0001] The invention belongs to the technical field of high-precision positioning, and relates to a coordinate transformation method and a system thereof. Background technique [0002] High-precision positioning technology is in wide demand around the world. Satellite positioning accuracy can no longer meet the needs of users in specific occasions. UWB high-precision positioning technology has emerged as the times require. At present, the solutions provided by various UWB positioning providers The required maps are drawn separately in areas that require high-precision positioning, and the positioning area is not too large. The coordinate system used in the map is a Cartesian coordinate system, but the map that has a large number of customer needs is a map that uses GPS latitude and longitude. This situation is more obvious among group customers. In this case, a mutual conversion method between Cartesian coordinates and GPS latitude and longitude is required ...

AI Technical Summary

Problems solved by technology

[0003] In the prior art, a method for mutual conversion between Cartesian coordinates and GPS latitude and longitude is to use Mercator projection, first convert GPS latitude and longitude and Mercator projection coordinates to each other, and then convert Cartesian coordinates and Mercator projection coordinates to each other, thereby establishing Cartesian coordinates The method of mutual conversion with GPS latitude and longitude, such as the formation of the world map is this principle, but the problem is that the Mercator projection will produce deformation, the farther away from the reference latitude, the more severe the deformation, and the reference latitude of the Mercator projection is the equator, and this will lead to The farther you are from the equator, the larger the distance generated by the projection is than the actual distance. In this way, for a system that only establishes a Cartesian coordinate system based on the actual distance in a small range to determine the position, the Cartesian coordinates and GPS latitude and longitude will be converted to each other. produce a large positional deviation

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