A study on factors for determination of elevation mask and CNR Mask on DGPS reference station

According to the recommendation of IALA, a 5~10 degree elevation mask is used in the DGPS reference station. An elevation mask filters out signals from satellites below a certain angle of elevation above the horizon, to prevent them from using noisy signals. A CNR Mask which is used for similar purposes, filters out signals below a certain value of CNR. Using these masks is effective in the production and accuracy of pseudorange correction in the DGPS reference station. In this study we analyze factors to determine of each mask value by measuring the noise and the DGPS position accuracy according to the change of elevation Mask and CNR Mask.