Estimation and Analysis of Modernized GPS C1X Differential Hardware Delay

The aim of this paper is to estimate and analyze the modernized signal C1X and the legacy signal C2W satellite differential hardware delay (DCBP1 - CXs). To this end, GPS data from a network consisting of 35 globally distributed IGS stations is used to estimate satellites C1C-C2W differential hardware delay (DCBP1 - C1s) using three methods. The first method is based on the direct estimation from Rinex data, the second method is based on Precise Point Positioning technique, and the third method is based on satellite clock analysis. The estimated values using the three methods are verified by comparing with the published values by IGS analysis centers (COD, DLR, and CAS). It is shown that the estimated values of DCBP1 - C1s using the three methods are comparable with the published values from the IGS analysis centers. The same three methods are then used to estimate C1X-C2W differential hardware delay (DCBP1 - CXs). The estimated values are then compared with the published values from DLR analysis center. It is shown that the estimated values of DCBP1 - CXs using the three methods are consistent with each other and with the DLR published values and they are in the range of ± 0.5ns for all modernized Block III satellites.