Abstract:This paper studies the stochastic model of DCB for GNSS systems by post-processing phase smoothed code data. To resolve the problem of estimating the uncertainty of the parameters of the weight of the elevation angle and the equal-accuracy, the paper presents a weighted method, i.e., variation coefficient weighting, to effectively influence the stochastic model. The index weights are determined according to the decision matrix of the index value of the evaluation object. Preliminary results show that: 1) The fitting precision of the model is related to observation data and the station location. The more stable the ionospheric variation of the station position and the adequacy of the observational data, the better the model fitting accuracy. 2) The model fitting accuracy is better than by the weight of elevation angle using variation coefficient weighting. 3) In the accuracy and stability of parameter estimation, the variation coefficient weighting method is superior to the method of the weight of elevation angle, and the calculation accuracy of single-day data can be improved by 0.2 ns.