Patent ID: 8665146

Claim:
A calculation method of determining an estimated value of the amount of zenith troposphere delay comprising: two or more amendment areas which satisfy the same weather condition in a service area is set up by an entrepreneur, in this amendment area, point A and at least one reference point B which offers correction information of the amount of zenith troposphere delay to be used by a user located in point A (user point) are set up, an estimated value ZTD B of said amount of zenith troposphere delay in this reference point B is calculated, a difference between the estimated value of the amount of zenith troposphere delay in said reference point B and a MOPS model function f ZTD (B) of the amount of zenith troposphere delay in reference point B is calculated, subsequently, the difference between the estimated value of the amount of zenith troposphere delay in said reference point B and said model function f ZTD (B) of the amount of the amount of zenith troposphere delay in reference point B is transmitted to said point A (user point) in said amendment area as correction information for calculating the estimated value of the amount of zenith troposphere delay in point A, said correction information are obtained by the user located in point A (user point), a model function f ZTD (A) of the amount of zenith troposphere delay in point A is corrected by this obtained correction information, an estimated value ZTD A of the amount of zenith troposphere delay in said point A to be used by the user located in point A (user point) is calculated by this corrected model function f ZTD (A) of the amount of zenith troposphere delay in point A, when two or more said reference points B are installed, estimated value ZTD B of the amount of zenith troposphere delay in each reference point B is calculated, respectively, two or more of these calculated estimated value of the amount of zenith troposphere delay, weight attachment is performed by the weight attachment function which consists of the distance and altitude difference of said point A and said each reference point B, and subsequently, the one amount of zenith troposphere delay is calculated by interpolating.