Global broadcast ionospheric time delay correction method and device based on single broadcast coefficient

The invention discloses a global broadcast ionosphere time delay correction method and device based on a single broadcast coefficient, and the method comprises the steps: constructing a full-rank multi-GNSS precise single-point positioning model, and achieving the extraction of ionosphere delay observation; a single-layer global ionosphere spherical harmonic function model is constructed according to the ionosphere delay observed quantity, and the daily mean value of the global ionosphere total electron content is solved; resolving a global broadcast ionosphere function model based on the daily mean of the global ionosphere total electron content, and obtaining solidification parameters of the global broadcast ionosphere function model; broadcasting the daily mean value of the global ionosphere total electron content as an ionosphere time delay correction parameter; and calculating an ionosphere delay correction number by using the ionosphere delay correction parameter and the solidification parameter of the