Estimation of PCO and PCV Parameters by Numerical Integration

For improving the quality of the estimation of three-dimensional coordinates of a point on the surface of the Earth, it is necessary that the errors derived from the variation of the GNSS receiver antenna's phase center be known and modeled. The modeling depends on the knowledge of parameters associated to the location of the phase center, PCO and PCV, which are determined through calibration proceedings in absolute or relative character. In this work, relative calibrations data, conducted by BCAL/UFPR, of the Leica AX 1202GG antenna, that use the WaSoft/Kalib calibration program, were utilized. PCO parameters, established by the program, are considered as initial conditions and propagated, by numeric integration, from an initial date until a final date. Based on propagated PCO parameters, new PCV parameters are also determined for the antenna. The predicted parameters are compared to the calibrated parameters for the same epoch. The results show maximum discrepancies just over 4 mm for the vertical component PCO vector and 5.5 mm for the PCV when calibration campaigns affected by precipitation are considered. Utilizing campaigns with no precipitation occurrence, the maximum results to the PCO and PCV discrepancies do not exceed 1.5 and 2.2 mm, respectively.

Keywords:
PCO and PCV Parameters; Numerical Integration; WaSoft/Kalib